Problem Given a string s consisting only of characters a, b and c. Return the number of substrings containing at least one occurrence of all these characters a, b and c. link Example 1: Input: s = "ab
Problem You are given two strings, s1 and s2. Your task is to find the smallest substring in s1 such that s2 appears as a subsequence within that substring. The characters of s2 must appear in the sa
Problem Given two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in t (including duplicates) is included in the window. If there is
Problem You are given a string s and an integer k. You can choose any character of the string and change it to any other uppercase English character. You can perform this operation at most k times. Re
Problem Given a string str and an integer K, return the length of the longest substring containing at most K distinct characters. A substring is a continuous part of the string. You cannot skip chara
Problem You are visiting a farm that has a single row of fruit trees arranged from left to right. The trees are represented by an integer array fruits where fruits[i] is the type of fruit the i<sup>th
Problem Given a binary array nums and an integer k, return the maximum number of consecutive 1's in the array if you can flip at most k 0's. (link) Example 1: Input: nums = [1,1,1,0,0,0,1,1,1,1,0], k
Problem Find the length of the longest substring without repeating characters. A substring is a continuous part of a string; characters cannot be skipped. View the problem on LeetCode. Examples Inp
Problem Given an array cardPoints, pick exactly k cards. Each pick must come from the beginning or the end of the remaining row. Return the maximum total score. (link) Examples cardPoints k Maximum