title
2 Sum Problem | 2 types of the same problem for Interviews | Brute-Better-Optimal

description
Notes/C++/Java/Python codes: https://takeuforward.org/data-structure/two-sum-check-if-a-pair-with-given-sum-exists-in-array/ Problem links. 2 Sum: https://bit.ly/3Iu7zMu We have solved the problem, and we have gone from brute force and ended with the most optimal solution. Full Course: https://bit.ly/tufA2ZYt You can follow me across social media, all my handles are below: Linkedin/Instagram/Telegram: https://linktr.ee/takeUforward 0:00 Introduction of course

detail
{'title': '2 Sum Problem | 2 types of the same problem for Interviews | Brute-Better-Optimal', 'heatmap': [{'end': 600.609, 'start': 556.325, 'weight': 0.769}, {'end': 661.419, 'start': 616.261, 'weight': 0.735}], 'summary': "The strybus a2z dsa course claims to be the world's most in-depth, covering 456 modules and 400+ problems, ensuring the ability to crack any dsalgo round or interview. additionally, the video covers the two sum problem, presenting brute force and hashing solutions, and demonstrates efficient element finding using hashing and a two pointer approach.", 'chapters': [{'end': 41.637, 'segs': [{'end': 41.637, 'src': 'embed', 'start': 3.24, 'weight': 0, 'content': [{'end': 4.481, 'text': 'Hey everyone, welcome back to the channel.', 'start': 3.24, 'duration': 1.241}, {'end': 5.882, 'text': 'I hope you guys are doing extremely well.', 'start': 4.501, 'duration': 1.381}, {'end': 9.124, 'text': 'So this is another video from the Strybus A2Z DSA course.', 'start': 6.242, 'duration': 2.882}, {'end': 12.927, 'text': "Just in case you're for the first time here, this is world's most in-depth course in DSL.", 'start': 9.525, 'duration': 3.402}, {'end': 17.471, 'text': 'But why do I say that? Because in this course, I will be covering 456 modules.', 'start': 12.947, 'duration': 4.524}, {'end': 20.972, 'text': 'By the end of the course, we would have solved 400 plus problems.', 'start': 17.511, 'duration': 3.461}, {'end': 23.293, 'text': 'in dsalgo, you can go across the entire internet.', 'start': 20.972, 'duration': 2.321}, {'end': 25.113, 'text': 'you can buy any of the paid courses.', 'start': 23.293, 'duration': 1.82}, {'end': 28.294, 'text': 'none of them will be teaching dsalgo in such depth.', 'start': 25.113, 'duration': 3.181}, {'end': 34.776, 'text': 'so something that i can give you as a guarantee is, once you complete this entire course, you can crack any of the dsalgo rounds it,', 'start': 28.294, 'duration': 6.482}, {'end': 38.457, 'text': 'any of the interviews it, any of the companies in any part of the world.', 'start': 34.776, 'duration': 3.681}, {'end': 41.637, 'text': 'so till now we have covered till step 3.1.', 'start': 38.457, 'duration': 3.18}], 'summary': 'Strybus a2z dsa course covers 456 modules and 400+ problems, guaranteeing expertise for cracking any dsalgo round or interview.', 'duration': 38.397, 'max_score': 3.24, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k3240.jpg'}], 'start': 3.24, 'title': 'Strybus a2z dsa course', 'summary': "Introduces the strybus a2z dsa course, claiming to be the world's most in-depth course in dsl, covering 456 modules and solving 400 plus problems, ensuring the ability to crack any dsalgo round or interview.", 'chapters': [{'end': 41.637, 'start': 3.24, 'title': 'Strybus a2z dsa course', 'summary': "Introduces the strybus a2z dsa course, claiming to be the world's most in-depth course in dsl, covering 456 modules and solving 400 plus problems, ensuring the ability to crack any dsalgo round or interview.", 'duration': 38.397, 'highlights': ['The Strybus A2Z DSA course covers 456 modules, making it the most in-depth course in DSL.', 'By the end of the course, 400 plus problems would have been solved, demonstrating comprehensive coverage of dsalgo.', "Completing the entire course guarantees the ability to crack any dsalgo round or interview, underlining the course's effectiveness.", 'The course has covered till step 3.1, providing a progress update on the content covered.']}], 'duration': 38.397, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k3240.jpg', 'highlights': ['The Strybus A2Z DSA course covers 456 modules, making it the most in-depth course in DSL.', 'By the end of the course, 400 plus problems would have been solved, demonstrating comprehensive coverage of dsalgo.', "Completing the entire course guarantees the ability to crack any dsalgo round or interview, underlining the course's effectiveness.", 'The course has covered till step 3.1, providing a progress update on the content covered.']}, {'end': 537.693, 'segs': [{'end': 69.865, 'src': 'embed', 'start': 41.637, 'weight': 0, 'content': [{'end': 48.019, 'text': 'we will be starting with step 3.2, and the problem that we will be solving in this particular video is the two sum problem.', 'start': 41.637, 'duration': 6.382}, {'end': 50.36, 'text': 'So what does this particular problem see?', 'start': 48.539, 'duration': 1.821}, {'end': 54.721, 'text': "Now, this particular problem has two different varieties and I'll be covering both of them.", 'start': 50.48, 'duration': 4.241}, {'end': 56.121, 'text': 'The first one is very simple.', 'start': 54.981, 'duration': 1.14}, {'end': 61.343, 'text': "You'll be given an array and the array will be containing integers and you'll be given a target value.", 'start': 56.561, 'duration': 4.782}, {'end': 69.865, 'text': 'Your task is to tell me, does there exist two elements A and B from the array such that if you add them up, you get this particular sum.', 'start': 61.703, 'duration': 8.162}], 'summary': 'Solving the two sum problem with step 3.2, covering two varieties of the problem.', 'duration': 28.228, 'max_score': 41.637, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k41637.jpg'}, {'end': 275.45, 'src': 'embed', 'start': 240.482, 'weight': 1, 'content': [{'end': 242.484, 'text': "It's a very simple brute force solution.", 'start': 240.482, 'duration': 2.002}, {'end': 249.888, 'text': 'What is the time complexity? n square because for every element, you are checking with every other element.', 'start': 242.884, 'duration': 7.004}, {'end': 252.269, 'text': 'For every element, you are checking with every other element.', 'start': 250.208, 'duration': 2.061}, {'end': 255.311, 'text': 'So can I optimize them further? The answer to that is yes.', 'start': 252.67, 'duration': 2.641}, {'end': 258.851, 'text': "Imagine you add 2, you're checking with 6, 5, 8, 11.", 'start': 255.751, 'duration': 3.1}, {'end': 260.474, 'text': 'So 2 and 6 are already checked.', 'start': 258.853, 'duration': 1.621}, {'end': 265.737, 'text': 'If you carefully observe, 2 and 6 are already checked as 2 elements.', 'start': 260.534, 'duration': 5.203}, {'end': 275.45, 'text': "Now when you add 6, is there a point on again checking for 2? Because even if you again check for 2, it's like again 2 and 6.", 'start': 266.277, 'duration': 9.173}], 'summary': 'Brute force solution with time complexity o(n^2); suggests optimization by avoiding redundant checks.', 'duration': 34.968, 'max_score': 240.482, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k240482.jpg'}, {'end': 334.722, 'src': 'embed', 'start': 306.075, 'weight': 2, 'content': [{'end': 310.696, 'text': "So the interviewer will not be happy with the brute force solution and he'll ask you to optimize this.", 'start': 306.075, 'duration': 4.621}, {'end': 313.117, 'text': 'This is when you go to the better solution.', 'start': 311.156, 'duration': 1.961}, {'end': 315.758, 'text': 'The better solution is going to use hashing.', 'start': 313.417, 'duration': 2.341}, {'end': 318.158, 'text': 'And what is my thought process behind it?', 'start': 316.478, 'duration': 1.68}, {'end': 327.341, 'text': "It's more like I'm doing an n square to kind of trim it down to somewhere near about n or n log n or somewhere which is better than n square.", 'start': 318.719, 'duration': 8.622}, {'end': 334.722, 'text': 'When I think about a big O of n approach, it tells me that means iterating on an element once.', 'start': 327.841, 'duration': 6.881}], 'summary': 'Interviewer expects optimized solution. better solution uses hashing to reduce time complexity to n or n log n.', 'duration': 28.647, 'max_score': 306.075, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k306075.jpg'}, {'end': 370.843, 'src': 'embed', 'start': 347.929, 'weight': 3, 'content': [{'end': 355.232, 'text': "If I'm looking for one more element, what will it be? If I'm looking for 14, if I have 8, the other element will be 6.", 'start': 347.929, 'duration': 7.303}, {'end': 356.132, 'text': 'Simple mathematics.', 'start': 355.232, 'duration': 0.9}, {'end': 363.615, 'text': "If I'm looking for 6, how do I figure this out? Does 6 exist in the array or not? So we say, yes, it does.", 'start': 356.632, 'duration': 6.983}, {'end': 366.999, 'text': 'But how do you figure it out easily? You know the technique hashing.', 'start': 363.975, 'duration': 3.024}, {'end': 370.843, 'text': 'If you would have stored it somewhere that six is there, six is there.', 'start': 367.64, 'duration': 3.203}], 'summary': 'Using hashing to quickly find elements in an array.', 'duration': 22.914, 'max_score': 347.929, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k347929.jpg'}], 'start': 41.637, 'title': 'Two sum problem and hashing solutions', 'summary': 'Covers the two sum problem, including brute force and hashing solutions, with a focus on time complexity, and also demonstrates the use of hashing to efficiently find specific elements in an array, such as 12 and 8, along with their indexes.', 'chapters': [{'end': 347.589, 'start': 41.637, 'title': 'Two sum problem: brute force and hashing solutions', 'summary': 'Discusses the two sum problem, which involves finding pairs of elements in an array that sum up to a given target, with the first variety determining if a sum exists and the second variety requiring the indexes of the two elements. it covers the brute force solution with a time complexity of o(n^2) and introduces the optimization using hashing to achieve a better time complexity.', 'duration': 305.952, 'highlights': ['The chapter discusses the two sum problem, which involves finding pairs of elements in an array that sum up to a given target, with the first variety determining if a sum exists and the second variety requiring the indexes of the two elements.', 'It covers the brute force solution with a time complexity of O(n^2).', 'Introduces the optimization using hashing to achieve a better time complexity.']}, {'end': 537.693, 'start': 347.929, 'title': 'Hashing for finding elements', 'summary': 'Illustrates using hashing to efficiently find elements in an array, demonstrating a step-by-step process to find specific elements, such as 12 and 8, and their respective indexes.', 'duration': 189.764, 'highlights': ['Using hashing to quickly determine the presence of elements in an array, such as finding if 6 is present, and demonstrating the efficiency of this technique in finding the required elements in the array.', 'Step-by-step process of finding specific elements in the array, such as calculating the required number to reach a sum and identifying the indexes of the found elements.']}], 'duration': 496.056, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k41637.jpg', 'highlights': ['The chapter discusses the two sum problem, involving finding pairs of elements in an array that sum up to a given target', 'Covers the brute force solution with a time complexity of O(n^2)', 'Introduces the optimization using hashing to achieve a better time complexity', 'Using hashing to quickly determine the presence of elements in an array', 'Demonstrating the efficiency of hashing technique in finding the required elements in the array', 'Step-by-step process of finding specific elements in the array']}, {'end': 1091.433, 'segs': [{'end': 600.929, 'src': 'heatmap', 'start': 538.073, 'weight': 2, 'content': [{'end': 539.974, 'text': "Once you've done, you stop the iteration.", 'start': 538.073, 'duration': 1.901}, {'end': 550.619, 'text': "And if you have completed the iteration and you do not find any existence where you'd have got two elements, then you return no, very simple.", 'start': 540.314, 'duration': 10.305}, {'end': 552.381, 'text': "so let's quickly code the better solution.", 'start': 550.619, 'duration': 1.762}, {'end': 554.863, 'text': 'by the way, the problem link will be in the description.', 'start': 552.381, 'duration': 2.482}, {'end': 556.325, 'text': 'so we need a map.', 'start': 554.863, 'duration': 1.462}, {'end': 562.431, 'text': "so let's take a map at first and then we will be simply going across this one.", 'start': 556.325, 'duration': 6.106}, {'end': 568.197, 'text': 'can i say my first element is this how much more do i require?', 'start': 562.431, 'duration': 5.766}, {'end': 572.378, 'text': 'can i say i require more is target Minus 8..', 'start': 568.197, 'duration': 4.181}, {'end': 576.021, 'text': "Can I see if I have to look in the map? I'll say map.find more.", 'start': 572.378, 'duration': 3.643}, {'end': 579.924, 'text': "Are you there in the map? If you're in the map, then you'll not be pointing to the last rate return.", 'start': 576.201, 'duration': 3.723}, {'end': 583.226, 'text': "If that's the case, we will be returning yes.", 'start': 580.224, 'duration': 3.002}, {'end': 590.171, 'text': 'Or else, you just keep on going.', 'start': 587.649, 'duration': 2.522}, {'end': 600.609, 'text': 'And if you keep on going, what will you do? You will say npv map of this particular guy who is this number and is this market at the index.', 'start': 590.552, 'duration': 10.057}, {'end': 600.929, 'text': "That's it.", 'start': 600.649, 'duration': 0.28}], 'summary': "Iterate to find two elements in map, return 'yes' if found, 'no' otherwise.", 'duration': 62.856, 'max_score': 538.073, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k538073.jpg'}, {'end': 661.419, 'src': 'heatmap', 'start': 616.261, 'weight': 0.735, 'content': [{'end': 617.821, 'text': 'more and the index i.', 'start': 616.261, 'duration': 1.56}, {'end': 618.301, 'text': 'Quite simple.', 'start': 617.821, 'duration': 0.48}, {'end': 621.222, 'text': 'If they need the index, this is how you return.', 'start': 618.421, 'duration': 2.801}, {'end': 625.603, 'text': 'If they need yes or no, this is how you do.', 'start': 621.922, 'duration': 3.681}, {'end': 628.123, 'text': 'So, in this way, you can solve both the varieties.', 'start': 625.863, 'duration': 2.26}, {'end': 635.384, 'text': 'So for the variety 2, you can write the hashing solution on leetcode and then you can quickly go and run this,', 'start': 629.023, 'duration': 6.361}, {'end': 638.165, 'text': 'and it should be running on leetcode as well.', 'start': 635.384, 'duration': 2.781}, {'end': 640.045, 'text': "Let's quickly submit this as well.", 'start': 638.845, 'duration': 1.2}, {'end': 641.265, 'text': 'Cool, it does run.', 'start': 640.545, 'duration': 0.72}, {'end': 645.587, 'text': "Okay, so what is the time complexity of such an approach? It's very simple.", 'start': 642.005, 'duration': 3.582}, {'end': 648.028, 'text': "It's Beagle of n.", 'start': 646.107, 'duration': 1.921}, {'end': 652.432, 'text': "I can say n if you're assuming the map to work in Beagle of 1.", 'start': 648.028, 'duration': 4.404}, {'end': 655.754, 'text': "If the map works in logarithmic of n, then it's log n.", 'start': 652.432, 'duration': 3.322}, {'end': 657.315, 'text': 'Depends on which map you take.', 'start': 655.754, 'duration': 1.561}, {'end': 659.917, 'text': 'I have already discussed an entire complexity lecture.', 'start': 657.496, 'duration': 2.421}, {'end': 661.419, 'text': 'You can go over there and watch.', 'start': 659.978, 'duration': 1.441}], 'summary': 'Hashing solution on leetcode for variety 2 runs successfully with time complexity of o(n) or o(log n) depending on the map used.', 'duration': 45.158, 'max_score': 616.261, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k616261.jpg'}, {'end': 648.028, 'src': 'embed', 'start': 617.821, 'weight': 3, 'content': [{'end': 618.301, 'text': 'Quite simple.', 'start': 617.821, 'duration': 0.48}, {'end': 621.222, 'text': 'If they need the index, this is how you return.', 'start': 618.421, 'duration': 2.801}, {'end': 625.603, 'text': 'If they need yes or no, this is how you do.', 'start': 621.922, 'duration': 3.681}, {'end': 628.123, 'text': 'So, in this way, you can solve both the varieties.', 'start': 625.863, 'duration': 2.26}, {'end': 635.384, 'text': 'So for the variety 2, you can write the hashing solution on leetcode and then you can quickly go and run this,', 'start': 629.023, 'duration': 6.361}, {'end': 638.165, 'text': 'and it should be running on leetcode as well.', 'start': 635.384, 'duration': 2.781}, {'end': 640.045, 'text': "Let's quickly submit this as well.", 'start': 638.845, 'duration': 1.2}, {'end': 641.265, 'text': 'Cool, it does run.', 'start': 640.545, 'duration': 0.72}, {'end': 645.587, 'text': "Okay, so what is the time complexity of such an approach? It's very simple.", 'start': 642.005, 'duration': 3.582}, {'end': 648.028, 'text': "It's Beagle of n.", 'start': 646.107, 'duration': 1.921}], 'summary': 'Provided a simple solution for two varieties, including time complexity of o(n).', 'duration': 30.207, 'max_score': 617.821, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k617821.jpg'}, {'end': 690.77, 'src': 'embed', 'start': 663.62, 'weight': 1, 'content': [{'end': 667.962, 'text': 'And b go of n when we take an unordered map in the best and average case.', 'start': 663.62, 'duration': 4.342}, {'end': 674.284, 'text': 'In the worst case of unordered map, it can go up to b go of n squared, the complexity.', 'start': 668.322, 'duration': 5.962}, {'end': 678.865, 'text': 'Because find takes b go of n in the worst case in unordered.', 'start': 674.604, 'duration': 4.261}, {'end': 685.108, 'text': "Got it? What about this piece? I'm using a hash map where we are dumping every element, every element.", 'start': 679.226, 'duration': 5.882}, {'end': 688.889, 'text': "And if you're dumping every element, we know it's going to store everything.", 'start': 685.428, 'duration': 3.461}, {'end': 690.77, 'text': "So it's a b go of n.", 'start': 689.189, 'duration': 1.581}], 'summary': 'In the worst case, unordered map complexity is o(n^2) due to find taking o(n). using a hash map to store every element results in o(n) complexity.', 'duration': 27.15, 'max_score': 663.62, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k663620.jpg'}, {'end': 727.639, 'src': 'embed', 'start': 701.803, 'weight': 0, 'content': [{'end': 707.05, 'text': "The only thing that they can drill you is they might ask you, hey, you're not allowed to use the map data structure.", 'start': 701.803, 'duration': 5.247}, {'end': 709.633, 'text': 'Can you solve this without using the map data structure?', 'start': 707.37, 'duration': 2.263}, {'end': 711.214, 'text': "this is where you'll be like.", 'start': 710.154, 'duration': 1.06}, {'end': 716.456, 'text': 'okay, maybe I have a slightly better solution, not much slightly better solution.', 'start': 711.214, 'duration': 5.242}, {'end': 719.997, 'text': 'And that solution will be using two pointer approach.', 'start': 716.816, 'duration': 3.181}, {'end': 721.337, 'text': "It's a very simple one.", 'start': 720.297, 'duration': 1.04}, {'end': 724.398, 'text': 'So there is no particular thought process behind it.', 'start': 721.777, 'duration': 2.621}, {'end': 727.639, 'text': "It's a very, very simple, greedy approach, greedy approach.", 'start': 724.598, 'duration': 3.041}], 'summary': 'Solving problem without using map data structure, using two pointer approach for a slightly better solution.', 'duration': 25.836, 'max_score': 701.803, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k701803.jpg'}, {'end': 926.627, 'src': 'embed', 'start': 898.708, 'weight': 4, 'content': [{'end': 901.31, 'text': 'two, because you have to store it in some other data structure.', 'start': 898.708, 'duration': 2.602}, {'end': 902.09, 'text': 'then you have to sort it.', 'start': 901.31, 'duration': 0.78}, {'end': 905.212, 'text': "So it's not an optimal solution for the variety two.", 'start': 902.51, 'duration': 2.702}, {'end': 913.116, 'text': 'For the variety one, where you just have to tell me yes or no, I can use this because we are no more using a map data structure.', 'start': 905.552, 'duration': 7.564}, {'end': 917.219, 'text': "We're just using sorting and then we're using a traversal in order to find it.", 'start': 913.457, 'duration': 3.762}, {'end': 920.401, 'text': "so let's jump into the editor and try to code this up again.", 'start': 917.759, 'duration': 2.642}, {'end': 926.627, 'text': 'the problem link will be in the description, so you can keep the left pointer as zero and the right pointer of the last index, which is n minus one.', 'start': 920.401, 'duration': 6.226}], 'summary': 'Using sorting and traversal for variety one, with problem link provided.', 'duration': 27.919, 'max_score': 898.708, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k898708.jpg'}], 'start': 538.073, 'title': 'Finding two elements efficiently', 'summary': 'Discusses the process of efficiently finding two elements during an iteration using a map, providing solutions for both varieties. it covers the time complexity of using map data structure and introduces a two pointer approach with o(n) time complexity and o(1) space complexity, suitable for variety one problems.', 'chapters': [{'end': 641.265, 'start': 538.073, 'title': 'Finding two elements in an iteration', 'summary': "Discusses the process of finding two elements during an iteration using a map and checking for their presence, returning 'yes' if found, and 'no' if not, providing a solution for both the varieties.", 'duration': 103.192, 'highlights': ["The process involves using a map to check for the existence of two elements during an iteration, returning 'yes' if found and 'no' if not.", "The solution provided can handle both the varieties of returning the index of the elements or a 'yes' or 'no' response.", 'The speaker mentions coding the better solution and submitting it to a platform like LeetCode for verification.']}, {'end': 1091.433, 'start': 642.005, 'title': 'Map data structure and two pointer approach', 'summary': 'Covers the time complexity of using map data structure and explains a two pointer approach with a time complexity of o(n) and space complexity of o(1), suitable for solving variety one problems.', 'duration': 449.428, 'highlights': ['The time complexity is O(n) for the two pointer approach, and O(n log n) for sorting, with a space complexity of O(1) if not considering the distorted array.', 'Using a map data structure can result in different time complexities, such as O(n) for unordered map in best and average case, and O(n^2) in the worst case.', 'The two pointer approach provides an optimal solution for variety one problems and utilizes a greedy approach with a time complexity of O(n) and space complexity of O(1).']}], 'duration': 553.36, 'thumbnail': 'https://coursnap.oss-ap-southeast-1.aliyuncs.com/video-capture/UXDSeD9mN-k/pics/UXDSeD9mN-k538073.jpg', 'highlights': ['The two pointer approach has a time complexity of O(n) and space complexity of O(1)', 'Using a map data structure can result in time complexities of O(n) for unordered map in best and average case, and O(n^2) in the worst case', "The process involves using a map to check for the existence of two elements during an iteration, returning 'yes' if found and 'no' if not", "The solution provided can handle both the varieties of returning the index of the elements or a 'yes' or 'no' response", 'The two pointer approach provides an optimal solution for variety one problems and utilizes a greedy approach with a time complexity of O(n) and space complexity of O(1)', 'The speaker mentions coding the better solution and submitting it to a platform like LeetCode for verification']}], 'highlights': ['The Strybus A2Z DSA course covers 456 modules, making it the most in-depth course in DSL.', 'By the end of the course, 400 plus problems would have been solved, demonstrating comprehensive coverage of dsalgo.', "Completing the entire course guarantees the ability to crack any dsalgo round or interview, underlining the course's effectiveness.", 'The chapter discusses the two sum problem, involving finding pairs of elements in an array that sum up to a given target', 'The two pointer approach has a time complexity of O(n) and space complexity of O(1)', 'Introduces the optimization using hashing to achieve a better time complexity', 'Using a map data structure can result in time complexities of O(n) for unordered map in best and average case, and O(n^2) in the worst case']}