Permutations Leetcode Solution

The problem Permutations Leetcode Solution provides a simple sequence of integers and asks us to return a complete vector or array of all the permutations of the given sequence. So, before going into solving the problem. We should be familiar with permutations. So, a permutation is nothing but an arrangement …

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Longest Substring Without Repeating Characters

Given a string, we have to find the length of the longest substring without repeating characters. Let’s look into a few examples: Example pwwkew 3 Explanation: Answer is “wke” with length 3 aav 2 Explanation: Answer is “av” with length 2 Approach-1 for Longest Substring Without Repeating Characters  Brute Force  …

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Design a stack that supports getMin() in O(1) time and O(1) extra space

Design a stack that supports getMin() in O(1) time and O(1) extra space. Thus the special stack data structure must support all the operations of the stack like – void push() int pop() bool isFull() bool isEmpty() in constant time. Add an additional operation getMin() to return the minimum value …

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Reverse a linked list

Problem Statement The problem “reverse a linked list” states that we are given the head of the linked list. We have to reverse the linked list by changing the links between them and return the head of the reversed linked list. Example 10->20->30->40->NULL NULL<-10<-20<-30<-40 Explanation We have reversed the linked …

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