Koko Eating Bananas | Binary Search on the ANSWER | LeetCode 75 #56

Koko Eating Bananas (LeetCode 875) explained in Hindi — the canonical "binary search on the ANSWER" problem. Instead of searching the piles array, we binary-search the eating speed k: if speed k finishes in h hours, every faster speed does too (monotonicity). Full dry run, debugger-style C++ code walkthrough with every line's WHY, correctness proof, edge cases, and interview tips. Problem: https://leetcode.com/problems/koko-ea... What you will learn: Why binary search applies to the answer space, not the input array Monotonic predicate proof in plain words (faster can never be slower) Ceil-per-pile hours formula (p + k - 1) / k and why total/k is wrong Search bounds [1, max(piles)] and why max(piles) always works Answer-tracking convergence: ans = mid, right = mid - 1 C++ implementation with long long overflow safety Time O(n log maxPile), space O(1) Chapters: 00:00 Problem story: Koko, piles, guards, the one-pile-per-hour rule 04:00 Why not try k = 1, 2, 3... (the 1e9 trap) 08:00 Core idea: search the speedometer, not the roads 12:00 Hard part 1: why binary search on the answer 16:00 Hard part 2: monotonicity proof with live races 21:00 Hard part 3: ceil per pile, bounds, convergence 26:00 Full dry run on [3,6,7,11], h = 8 31:00 Debugger-style C++ walkthrough (every line: WHY) 38:00 Correctness proof + complexity 41:00 Edge cases (h == n, huge h, overflow) 44:00 Interview tips + pattern family #LeetCode75 #KokoEatingBananas #BinarySearch #DSAinHindi #CodingInterview #Placements #Cpp #AlgorithmExplained