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G-11. Detect a Cycle in an Undirected Graph using BFS | C++ | Java

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{'title': 'G-11. Detect a Cycle in an Undirected Graph using BFS | C++ | Java', 'heatmap': [{'end': 753.973, 'start': 706.692, 'weight': 0.825}], 'summary': 'Covers detecting cycles in undirected graphs using bfs and dfs, explaining the bfs algorithm, node visitation, and cycle detection, with a focus on time and space complexity, and emphasizes the importance of cycle detection.', 'chapters': [{'end': 64.673, 'segs': [{'end': 32.982, 'src': 'embed', 'start': 3.387, 'weight': 0, 'content': [{'end': 4.988, 'text': 'hey, everyone, welcome back to the channel.', 'start': 3.387, 'duration': 1.601}, {'end': 7.089, 'text': 'i hope you guys are doing extremely well.', 'start': 4.988, 'duration': 2.101}, {'end': 16.233, 'text': 'so in this video we are going to learn about detecting a cycle yes, cycle in an undirected very, very important in an undirected graph.', 'start': 7.089, 'duration': 9.144}, {'end': 20.235, 'text': 'so in this video we will be learning how to solve this using bfs.', 'start': 16.233, 'duration': 4.002}, {'end': 25.338, 'text': 'in the next we will be learning how to solve this using dfs now, since now, like till now,', 'start': 20.235, 'duration': 5.103}, {'end': 31.581, 'text': 'you have seen how to use bfs in order to solve matrix related problems or how to traverse in a graph.', 'start': 25.338, 'duration': 6.243}, {'end': 32.982, 'text': 'but how do you detect a cycle?', 'start': 31.581, 'duration': 1.401}], 'summary': 'Learn about detecting cycles in undirected graphs using bfs and dfs.', 'duration': 29.595, 'max_score': 3.387, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU3387.jpg'}], 'start': 3.387, 'title': 'Detecting cycles in undirected graphs', 'summary': 'Discusses the process of detecting cycles in an undirected graph using bfs and dfs, emphasizing the importance and key concepts of cycle detection.', 'chapters': [{'end': 64.673, 'start': 3.387, 'title': 'Detecting cycles in undirected graphs', 'summary': 'Discusses the process of detecting cycles in an undirected graph using bfs and dfs, addressing the importance and key concepts of cycle detection in a graph.', 'duration': 61.286, 'highlights': ['The importance of detecting cycles in an undirected graph using BFS and DFS is emphasized.', 'Explanation of the definition of a cycle in a graph and the criteria for identifying a cycle is provided.', 'The process of creating an adjacency list for a given graph is mentioned as a prerequisite for cycle detection.']}], 'duration': 61.286, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU3387.jpg', 'highlights': ['The importance of detecting cycles in an undirected graph using BFS and DFS is emphasized.', 'Explanation of the definition of a cycle in a graph and the criteria for identifying a cycle is provided.', 'The process of creating an adjacency list for a given graph is mentioned as a prerequisite for cycle detection.']}, {'end': 333.886, 'segs': [{'end': 145.606, 'src': 'embed', 'start': 65.134, 'weight': 0, 'content': [{'end': 73.079, 'text': 'What is BFS? It is nothing but a traversal technique where you start from a node and you visit all the nodes in that graph.', 'start': 65.134, 'duration': 7.945}, {'end': 75.381, 'text': 'So if you are starting from this node one, yes.', 'start': 73.54, 'duration': 1.841}, {'end': 78.263, 'text': 'what do you visit in the next step?', 'start': 76.542, 'duration': 1.721}, {'end': 86.226, 'text': 'you visit two, three, because they are at a distance of one or level one.', 'start': 78.263, 'duration': 7.963}, {'end': 89.827, 'text': 'at the next step you visit five, six, four.', 'start': 86.226, 'duration': 3.601}, {'end': 93.949, 'text': 'why? because they are at a distance of two.', 'start': 89.827, 'duration': 4.122}, {'end': 95.79, 'text': 'if you see they are at a distance of two.', 'start': 93.949, 'duration': 1.841}, {'end': 99.071, 'text': 'at the next time you visit this seven.', 'start': 95.79, 'duration': 3.281}, {'end': 101.432, 'text': 'so this is what the bfs traversal is.', 'start': 99.071, 'duration': 2.361}, {'end': 106.744, 'text': 'it goes in level wise, like level one, level two, level three.', 'start': 101.432, 'duration': 5.312}, {'end': 112.964, 'text': 'so basically, it visits simultaneously these two notes, Then these three nodes, then this node.', 'start': 106.744, 'duration': 6.22}, {'end': 119.369, 'text': 'This is what we call as BFS traversal, whereas DFS is different where you just go, go, go, go, go.', 'start': 113.324, 'duration': 6.045}, {'end': 121.19, 'text': 'So you go basically, okay.', 'start': 119.669, 'duration': 1.521}, {'end': 124.132, 'text': "What is the intuition of the algorithm? Let's understand.", 'start': 121.51, 'duration': 2.622}, {'end': 133.32, 'text': 'So we know BFS is nothing but a traversal technique, right? So imagine the first thing is one where you start it.', 'start': 124.793, 'duration': 8.527}, {'end': 135.201, 'text': 'from where?', 'start': 133.88, 'duration': 1.321}, {'end': 136.481, 'text': 'from one, where do you go?', 'start': 135.201, 'duration': 1.28}, {'end': 137.382, 'text': 'you go to two.', 'start': 136.481, 'duration': 0.901}, {'end': 139.423, 'text': 'you go to three at the same junction.', 'start': 137.382, 'duration': 2.041}, {'end': 145.606, 'text': 'remember this from one, you go to two and three at the same junction because they are at level one.', 'start': 139.423, 'duration': 6.183}], 'summary': 'Bfs is a traversal technique that visits nodes level-wise, with an example of visiting nodes 1, 2, 3, 5, 6, 4, and 7.', 'duration': 80.472, 'max_score': 65.134, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU65134.jpg'}, {'end': 285.621, 'src': 'embed', 'start': 261.76, 'weight': 1, 'content': [{'end': 268.003, 'text': 'And now if you are colliding in some portion, that will only be because there is something as a cycle.', 'start': 261.76, 'duration': 6.243}, {'end': 270.205, 'text': 'So what does the BFS algorithm state?', 'start': 268.364, 'duration': 1.841}, {'end': 277.708, 'text': 'If you remember well enough the BFS algorithm, the first step of the BFS algorithm is define a queue and insert the first node.', 'start': 270.705, 'duration': 7.003}, {'end': 280.47, 'text': 'So this is the first node or the source node.', 'start': 278.029, 'duration': 2.441}, {'end': 284.439, 'text': 'With the parent, you need to remember where it came from.', 'start': 281.434, 'duration': 3.005}, {'end': 285.621, 'text': 'Very, very important.', 'start': 284.68, 'duration': 0.941}], 'summary': 'Bfs algorithm defines queue, inserts first node, and tracks parent nodes.', 'duration': 23.861, 'max_score': 261.76, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU261760.jpg'}], 'start': 65.134, 'title': 'Breadth first search algorithm', 'summary': 'Explains the breadth first search (bfs) traversal technique in a graph, demonstrating level-wise traversal and the difference between bfs and dfs. it also covers the intuition, working, and steps involved in the bfs algorithm, highlighting the importance of creating a queue, defining the source node, and maintaining a visited array.', 'chapters': [{'end': 119.369, 'start': 65.134, 'title': 'Bfs traversal explained', 'summary': 'Explains breadth first search (bfs) traversal technique in a graph, starting from a node and visiting all nodes at different levels, demonstrating the concept of level-wise traversal and the difference between bfs and dfs.', 'duration': 54.235, 'highlights': ['BFS traversal visits nodes level-wise, starting from a node and visiting all nodes at a particular level before moving to the next level, illustrating the concept of distance or level in the traversal process.', 'The example demonstrates BFS traversal by visiting nodes 1, 2, 3 at level one, then visiting nodes 5, 6, 4 at level two, and finally visiting node 7 at level three, showcasing the level-wise approach with specific node sequences.', 'Contrasts BFS with DFS, highlighting the difference in traversal approach by emphasizing that BFS visits nodes simultaneously at each level, in contrast to the continuous traversal of DFS.']}, {'end': 333.886, 'start': 119.669, 'title': 'Understanding bfs algorithm', 'summary': 'Explains the intuition and working of the bfs algorithm using a step-by-step explanation of traversing a graph, highlighting the importance of creating a queue, defining the source node, and maintaining a visited array.', 'duration': 214.217, 'highlights': ['The BFS algorithm involves defining a queue, inserting the first node as the source node, and creating a visited array to mark the nodes as visited, except for the source node.', 'The algorithm emphasizes the importance of tracking the parent node and using a visited array to mark the nodes, as illustrated by the traversal from node one to nodes two and three.', 'The explanation delves into the traversal from nodes two and three to nodes five, six, and four, showcasing the practical application of the BFS algorithm in traversing a graph.']}], 'duration': 268.752, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU65134.jpg', 'highlights': ['BFS traversal visits nodes level-wise, demonstrating the concept of distance or level.', 'The example showcases the level-wise approach with specific node sequences.', 'Contrasts BFS with DFS, emphasizing the difference in traversal approach.', 'The BFS algorithm involves defining a queue and creating a visited array.', 'Emphasizes the importance of tracking the parent node and using a visited array.', 'Practical application of the BFS algorithm in traversing a graph is demonstrated.']}, {'end': 636.809, 'segs': [{'end': 364.364, 'src': 'embed', 'start': 333.886, 'weight': 0, 'content': [{'end': 335.567, 'text': 'how, how will you know this?', 'start': 333.886, 'duration': 1.681}, {'end': 341.355, 'text': 'you will go to the adjacency list and you will see what it is stored and you see two and three are stored.', 'start': 335.567, 'duration': 5.788}, {'end': 344.016, 'text': 'so you can go to two and you can go to three.', 'start': 341.355, 'duration': 2.661}, {'end': 346.938, 'text': 'so you go to two and you say it came from one.', 'start': 344.016, 'duration': 2.922}, {'end': 349.419, 'text': 'you go to three and you say it came from one.', 'start': 346.938, 'duration': 2.481}, {'end': 351.34, 'text': 'so one can go to two.', 'start': 349.419, 'duration': 1.921}, {'end': 354.582, 'text': 'the market has visited and put that into the queue.', 'start': 351.34, 'duration': 3.242}, {'end': 359.064, 'text': 'then you can go to three mark it as visited and put that into the queue.', 'start': 354.582, 'duration': 4.482}, {'end': 361.966, 'text': 'once this is done, we can just omit this.', 'start': 359.064, 'duration': 2.902}, {'end': 364.364, 'text': 'perfect. Now again, get the next cat.', 'start': 361.966, 'duration': 2.398}], 'summary': 'Using adjacency list, visit nodes 2 and 3 from node 1, mark as visited and queue them.', 'duration': 30.478, 'max_score': 333.886, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU333886.jpg'}, {'end': 410.381, 'src': 'embed', 'start': 380.551, 'weight': 1, 'content': [{'end': 382.271, 'text': 'Why will I go back to 1? I will not.', 'start': 380.551, 'duration': 1.72}, {'end': 385.433, 'text': "So I'll just go back to 5.", 'start': 382.772, 'duration': 2.661}, {'end': 386.973, 'text': "So I'll go to 5 and say visited.", 'start': 385.433, 'duration': 1.54}, {'end': 390.535, 'text': "And I'll insert 5 came from 2.", 'start': 386.993, 'duration': 3.542}, {'end': 398.354, 'text': "perfect so five came from two and five is visited let's omit this The next guy will be 3,1.", 'start': 390.535, 'duration': 7.819}, {'end': 399.695, 'text': 'So 3 came from 1.', 'start': 398.354, 'duration': 1.341}, {'end': 400.055, 'text': 'See this.', 'start': 399.695, 'duration': 0.36}, {'end': 401.496, 'text': 'Observe this.', 'start': 400.756, 'duration': 0.74}, {'end': 402.657, 'text': '3 came from 1.', 'start': 401.516, 'duration': 1.141}, {'end': 405.558, 'text': 'From 3, where can you go? You can go to 1.', 'start': 402.657, 'duration': 2.901}, {'end': 406.859, 'text': 'But you came from 1.', 'start': 405.558, 'duration': 1.301}, {'end': 408.3, 'text': 'You can go to 4.', 'start': 406.859, 'duration': 1.441}, {'end': 410.381, 'text': 'Yes You can go to 6.', 'start': 408.3, 'duration': 2.081}], 'summary': 'Traversal from 1 to 5, 5 visited, 3 came from 1, can go to 4 and 6.', 'duration': 29.83, 'max_score': 380.551, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU380551.jpg'}], 'start': 333.886, 'title': 'Breadth first search algorithm and cycle detection', 'summary': 'Illustrates the breadth first search (bfs) algorithm by traversing through an adjacency list, visiting and marking nodes, and omitting revisits, with quantifiable data of node relationships and traversals. it also discusses the bfs algorithm for detecting cycles in a graph, emphasizing the importance of detecting cycles and detailing the process of implementing the algorithm using c++ and java.', 'chapters': [{'end': 461.839, 'start': 333.886, 'title': 'Breadth first search algorithm', 'summary': 'Illustrates the breadth first search (bfs) algorithm by traversing through an adjacency list, visiting and marking nodes, and omitting revisits, with quantifiable data of node relationships and traversals.', 'duration': 127.953, 'highlights': ['Traversing the adjacency list, marking nodes as visited, and omitting revisits demonstrates the Breadth First Search algorithm in action.', "The algorithm's application is exemplified through specific node relationships and traversal sequences, showcasing the efficiency and functionality of the Breadth First Search approach.", 'The process involves efficiently marking nodes as visited and omitting revisits, contributing to a streamlined traversal method in the Breadth First Search algorithm.']}, {'end': 636.809, 'start': 461.839, 'title': 'Bfs algorithm detecting cycles', 'summary': 'Discusses the bfs algorithm for detecting cycles in a graph, emphasizing the importance of detecting cycles and detailing the process of implementing the algorithm using c++ and java.', 'duration': 174.97, 'highlights': ['The chapter emphasizes the importance of detecting cycles in a graph and details the process of implementing the BFS algorithm for cycle detection using C++ and Java.', 'The algorithm involves traversing the graph using BFS and marking visited nodes to detect cycles, with a focus on maintaining a visited array and utilizing a queue to store node information.', 'The process includes initializing the source node, marking it as visited, and then traversing its adjacent nodes while maintaining a queue to track node relationships and detect cycles in a graph.']}], 'duration': 302.923, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU333886.jpg', 'highlights': ['The algorithm involves traversing the graph using BFS and marking visited nodes to detect cycles, with a focus on maintaining a visited array and utilizing a queue to store node information.', 'The process includes initializing the source node, marking it as visited, and then traversing its adjacent nodes while maintaining a queue to track node relationships and detect cycles in a graph.', 'Traversing the adjacency list, marking nodes as visited, and omitting revisits demonstrates the Breadth First Search algorithm in action.', "The algorithm's application is exemplified through specific node relationships and traversal sequences, showcasing the efficiency and functionality of the Breadth First Search approach.", 'The process involves efficiently marking nodes as visited and omitting revisits, contributing to a streamlined traversal method in the Breadth First Search algorithm.', 'The chapter emphasizes the importance of detecting cycles in a graph and details the process of implementing the BFS algorithm for cycle detection using C++ and Java.']}, {'end': 1071.161, 'segs': [{'end': 753.973, 'src': 'heatmap', 'start': 706.692, 'weight': 0.825, 'content': [{'end': 710.953, 'text': 'But this guy is visited because it came from 3.', 'start': 706.692, 'duration': 4.261}, {'end': 715.194, 'text': 'But why is this guy visited? Why is this guy visited? It did not come from seven.', 'start': 710.953, 'duration': 4.241}, {'end': 716.455, 'text': 'Why is this guy visited?', 'start': 715.495, 'duration': 0.96}, {'end': 724.117, 'text': 'If someone is visited, remember this if someone is visited and it did not come from it, if someone is visited,', 'start': 716.475, 'duration': 7.642}, {'end': 728.659, 'text': "that means it will come to else and it did not come from it, which means it's not the parent.", 'start': 724.117, 'duration': 4.542}, {'end': 730.66, 'text': 'Which means.', 'start': 730.099, 'duration': 0.561}, {'end': 732.766, 'text': 'It is a cycle.', 'start': 731.966, 'duration': 0.8}, {'end': 735.847, 'text': "If this guy is visited, it will come here and it's not the parent.", 'start': 733.286, 'duration': 2.561}, {'end': 739.648, 'text': "How did it visit himself? That's because it's a cycle.", 'start': 736.207, 'duration': 3.441}, {'end': 740.749, 'text': 'Someone else touched it.', 'start': 739.708, 'duration': 1.041}, {'end': 742.569, 'text': 'And if it is a cycle, you say cycle.', 'start': 741.049, 'duration': 1.52}, {'end': 748.131, 'text': "What else? If you just go across and you traverse everything, something like, I'll give you an example.", 'start': 742.589, 'duration': 5.542}, {'end': 753.973, 'text': 'If you traverse everything in sense, imagine you have something like 0, 1 node, 2 node, 3 node.', 'start': 748.211, 'duration': 5.762}], 'summary': 'The discussion involves traversing nodes and identifying cycles in a graph.', 'duration': 47.281, 'max_score': 706.692, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU706692.jpg'}, {'end': 740.749, 'src': 'embed', 'start': 716.475, 'weight': 1, 'content': [{'end': 724.117, 'text': 'If someone is visited, remember this if someone is visited and it did not come from it, if someone is visited,', 'start': 716.475, 'duration': 7.642}, {'end': 728.659, 'text': "that means it will come to else and it did not come from it, which means it's not the parent.", 'start': 724.117, 'duration': 4.542}, {'end': 730.66, 'text': 'Which means.', 'start': 730.099, 'duration': 0.561}, {'end': 732.766, 'text': 'It is a cycle.', 'start': 731.966, 'duration': 0.8}, {'end': 735.847, 'text': "If this guy is visited, it will come here and it's not the parent.", 'start': 733.286, 'duration': 2.561}, {'end': 739.648, 'text': "How did it visit himself? That's because it's a cycle.", 'start': 736.207, 'duration': 3.441}, {'end': 740.749, 'text': 'Someone else touched it.', 'start': 739.708, 'duration': 1.041}], 'summary': 'Identifying a cycle with the visited nodes in a recursive algorithm.', 'duration': 24.274, 'max_score': 716.475, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU716475.jpg'}, {'end': 887.946, 'src': 'embed', 'start': 856.835, 'weight': 0, 'content': [{'end': 865.219, 'text': 'so apparently you need to write like in terms of whenever there is a problem of multiple components, like, if you see over here in the example two,', 'start': 856.835, 'duration': 8.384}, {'end': 867.6, 'text': 'we have something like a multiple component thing.', 'start': 865.219, 'duration': 2.381}, {'end': 868.781, 'text': 'so what do you need to do?', 'start': 867.6, 'duration': 1.181}, {'end': 871.162, 'text': 'is you need to always write something like this?', 'start': 868.781, 'duration': 2.381}, {'end': 873.403, 'text': 'for i equal to the start?', 'start': 871.162, 'duration': 2.241}, {'end': 887.946, 'text': 'like if the nodes are one base, you start from one equal to n, you go like i, plus plus, okay, and over here what you do is you say if not visited i,', 'start': 873.403, 'duration': 14.543}], 'summary': 'Need to write code for handling multiple components in an example with a base of one and an increment of i++.', 'duration': 31.111, 'max_score': 856.835, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU856835.jpg'}, {'end': 952.984, 'src': 'embed', 'start': 921.236, 'weight': 4, 'content': [{'end': 925.418, 'text': "remember this you'll have a single visited array with all marked as zeros.", 'start': 921.236, 'duration': 4.182}, {'end': 925.819, 'text': 'so it will.', 'start': 925.418, 'duration': 0.401}, {'end': 935.225, 'text': 'whenever it goes to one and it finds zero, it goes and calls the detect cycle and the detect cycle will go and mark visit, visit, visit and visit.', 'start': 925.819, 'duration': 9.406}, {'end': 939.948, 'text': 'so all of these guys will be visited, correct, and it will not return a cycle.', 'start': 935.225, 'duration': 4.723}, {'end': 941.369, 'text': 'so apparently next time it will be two.', 'start': 939.948, 'duration': 1.421}, {'end': 944.042, 'text': 'so two will be already visited.', 'start': 942.441, 'duration': 1.601}, {'end': 946.702, 'text': "we've already visited the component that has two.", 'start': 944.042, 'duration': 2.66}, {'end': 952.984, 'text': 'next will be three already visited, four already visited, five not visited.', 'start': 946.702, 'duration': 6.282}], 'summary': 'Algorithm marks visited nodes, preventing cycle detection. two visited, rest not.', 'duration': 31.748, 'max_score': 921.236, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU921236.jpg'}], 'start': 636.809, 'title': 'Node visitation and cycle detection in graphs', 'summary': "Discusses the concept of node visitation in graph traversal and the detection of cycles using the breadth-first search algorithm. it highlights the marking of visited nodes, distinguishing cycles from unvisited nodes, and the identification of cycles in connected components, along with the algorithm's time complexity.", 'chapters': [{'end': 691.34, 'start': 636.809, 'title': 'Understanding node visitation in graph', 'summary': 'Explains the concept of node visitation in a graph traversal, highlighting how visited nodes are marked and the distinction between nodes forming a cycle and unvisited nodes.', 'duration': 54.531, 'highlights': ['When visiting nodes in a graph traversal, the distinction between previously visited nodes and unvisited nodes is crucial for understanding cycles and traversal paths.', 'Nodes in a graph are marked as visited when they are traversed, distinguishing between nodes forming a cycle and unvisited nodes.', 'Understanding node visitation in a graph traversal is essential for differentiating between nodes forming cycles and unvisited nodes, ensuring accurate traversal paths.']}, {'end': 1071.161, 'start': 691.34, 'title': 'Detecting cycles in graphs', 'summary': 'Explains the process of detecting cycles in a graph using the breadth-first search algorithm, emphasizing the identification of cycles in connected components and the time complexity of the algorithm.', 'duration': 379.821, 'highlights': ['The algorithm for detecting cycles in a graph involves utilizing breadth-first search to identify cycles in connected components.', 'The identification of cycles in connected components is emphasized, demonstrating the process of iteratively calling the cycle detection function for each component.', 'The time complexity of the algorithm is analyzed, with a focus on the number of nodes visited in the worst case scenario and the computation involving the summation of degrees.']}], 'duration': 434.352, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU636809.jpg', 'highlights': ['The algorithm for detecting cycles in a graph involves utilizing breadth-first search to identify cycles in connected components.', 'Understanding node visitation in a graph traversal is essential for differentiating between nodes forming cycles and unvisited nodes, ensuring accurate traversal paths.', 'The identification of cycles in connected components is emphasized, demonstrating the process of iteratively calling the cycle detection function for each component.', 'When visiting nodes in a graph traversal, the distinction between previously visited nodes and unvisited nodes is crucial for understanding cycles and traversal paths.', 'The time complexity of the algorithm is analyzed, with a focus on the number of nodes visited in the worst case scenario and the computation involving the summation of degrees.', 'Nodes in a graph are marked as visited when they are traversed, distinguishing between nodes forming a cycle and unvisited nodes.']}, {'end': 1210.74, 'segs': [{'end': 1107.26, 'src': 'embed', 'start': 1071.161, 'weight': 0, 'content': [{'end': 1074.083, 'text': 'you should remember the bfs algorithm i taught you.', 'start': 1071.161, 'duration': 2.922}, {'end': 1083.63, 'text': "so whatever time the bfs algorithm takes, it's going to take the same time, which is first, it will be n things twice of edge.", 'start': 1074.083, 'duration': 9.547}, {'end': 1084.691, 'text': 'why twice of edge?', 'start': 1083.63, 'duration': 1.061}, {'end': 1093.021, 'text': "because for every node you're traversing, for all its adjacent nodes, and the adjacent nodes is nothing but the degree.", 'start': 1084.691, 'duration': 8.33}, {'end': 1097.609, 'text': 'so the summation of all adjacent nodes is equal to the summation of degrees.', 'start': 1093.021, 'duration': 4.588}, {'end': 1107.26, 'text': "summation of adjacent nodes is what you're doing, which is equal to the summation of degree, which is equal to 2e in undirected graph,", 'start': 1097.609, 'duration': 9.651}], 'summary': 'Bfs algorithm takes time proportional to 2e in an undirected graph.', 'duration': 36.099, 'max_score': 1071.161, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU1071161.jpg'}, {'end': 1192.301, 'src': 'embed', 'start': 1165.192, 'weight': 2, 'content': [{'end': 1172.763, 'text': 'so you can just keep it simple and say that the complexity is near about n plus 2e and if you want to include the component thing, we go off n,', 'start': 1165.192, 'duration': 7.571}, {'end': 1178.872, 'text': "because in overall i'm going to touch everyone which is going to take this and then there's a for loop that is running not into,", 'start': 1172.763, 'duration': 6.109}, {'end': 1181.854, 'text': "Because overall I'll make sure I take this right?", 'start': 1179.272, 'duration': 2.582}, {'end': 1186.457, 'text': 'But that will be the time complexity and the space complexity for this one.', 'start': 1182.194, 'duration': 4.263}, {'end': 1192.301, 'text': 'So guys, I hope I was able to explain you how to detect a cycle in an undirected graph using BFS.', 'start': 1186.517, 'duration': 5.784}], 'summary': 'The time and space complexity for detecting a cycle in an undirected graph using bfs is near about n plus 2e.', 'duration': 27.109, 'max_score': 1165.192, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU1165192.jpg'}], 'start': 1071.161, 'title': 'Detecting cycles in undirected graph using bfs', 'summary': 'Explains the time complexity of detecting a cycle in an undirected graph using bfs as approximately n + 2e and the space complexity as o(n). it also emphasizes that the for loop runs only once for each component, simplifying the process.', 'chapters': [{'end': 1210.74, 'start': 1071.161, 'title': 'Detect cycle in undirected graph using bfs', 'summary': 'Explains the time complexity of detecting a cycle in an undirected graph using bfs as approximately n + 2e and the space complexity as o(n). it also emphasizes that the for loop runs only once for each component, simplifying the process.', 'duration': 139.579, 'highlights': ['The time complexity of detecting a cycle in an undirected graph using BFS is approximately n + 2e, where n represents the number of nodes and e represents the number of edges.', 'The space complexity for detecting a cycle in an undirected graph using BFS is O(n), primarily due to the utilization of a queue data structure and a visited array.', 'Emphasized that the for loop runs only once for each component, simplifying the process and contributing to the time complexity of the algorithm.']}], 'duration': 139.579, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/BPlrALf1LDU/pics/BPlrALf1LDU1071161.jpg', 'highlights': ['The time complexity of detecting a cycle in an undirected graph using BFS is approximately n + 2e', 'The space complexity for detecting a cycle in an undirected graph using BFS is O(n)', 'The for loop runs only once for each component, simplifying the process']}], 'highlights': ['The time complexity of detecting a cycle in an undirected graph using BFS is approximately n + 2e', 'The space complexity for detecting a cycle in an undirected graph using BFS is O(n)', 'The algorithm for detecting cycles in a graph involves utilizing breadth-first search to identify cycles in connected components', 'Understanding node visitation in a graph traversal is essential for differentiating between nodes forming cycles and unvisited nodes, ensuring accurate traversal paths', 'The process involves initializing the source node, marking it as visited, and then traversing its adjacent nodes while maintaining a queue to track node relationships and detect cycles in a graph']}