# Status Problem Level Completes Likes 1 Check If Student is eligible for an Attendance Reward Beginner % 0 2 Random character in a given string - Java Beginner % 0 3 Minimum Deletions to make the occurrence of each character unique. Hard % 1 4 Compare two version numbers of a software Medium % 1 5 Minimum number of times String A is repeated to such that B is substring of A Medium % 1 6 Find Lexicographically smallest or largest substring of size k Beginner % 0 7 Largest word in dictionary by removing a few characters from the given string Beginner % 0 8 Check if one string is a subsequence of another string. Beginner % 0 9 Print all steps to convert one string to another string Medium % 0 10 Lexicographically previous permutation With One swap Medium % 1 11 Hamming Distance between two given strings Beginner % 0 12 Find the maximum number present in a String Beginner % 0 13 Convert Prefix to Postfix Expression Medium % 0 14 Convert Postfix to Prefix Expression Medium % 0 15 Convert Integer to Roman Medium % 0 16 String to Integer (AtoI - ASCII to Integer) - Recursive Solution Medium % 0 17 Longest contiguous character in a given String - O(N) Solution Beginner % 0 18 Convert Postfix to Infix Expression Medium % 0 19 String to Integer (AtoI - ASCII to Integer) Beginner % 1 20 Longest substring with at most two unique characters Medium % 0 21 Convert Infix to Prefix Expression Medium % 0 22 Find duplicates Characters in the given String Beginner % 0 23 Convert Infix to Postfix Expression Medium % 0 24 Evaluation of Infix expressions Medium % 0 25 Convert Prefix to Infix Expression Medium % 0 26 Infix, Postfix and Prefix Notations/Expressions Beginner % 0 27 Valid Multiple Parentheses Medium % 1 28 Valid Brackets – Part 2 | Stack Method Beginner % 0 29 Given two strings validate the output string Beginner % 0 30 Generate all the strings of length n from 0 to k-1. Medium % 0 31 Find Largest and Smallest word in a given String Beginner % 0 32 Reverse the given String using Stack Beginner % 0 33 Check if two Strings are equal without using built-in function - Java Beginner % 0 34 Remove Vowels from a given String Beginner % 0 35 Find number of Distinct Permutations of a String Medium % 0 Check If Student is eligible for an Attendance Reward Random character in a given string - Java Minimum Deletions to make the occurrence of each character unique. Compare two version numbers of a software Minimum number of times String A is repeated to such that B is substring of A Find Lexicographically smallest or largest substring of size k Largest word in dictionary by removing a few characters from the given string Check if one string is a subsequence of another string. Print all steps to convert one string to another string Lexicographically previous permutation With One swap Hamming Distance between two given strings Find the maximum number present in a String Convert Prefix to Postfix Expression Convert Postfix to Prefix Expression Convert Integer to Roman String to Integer (AtoI - ASCII to Integer) - Recursive Solution Longest contiguous character in a given String - O(N) Solution Convert Postfix to Infix Expression String to Integer (AtoI - ASCII to Integer) Longest substring with at most two unique characters Convert Infix to Prefix Expression Find duplicates Characters in the given String Convert Infix to Postfix Expression Evaluation of Infix expressions Convert Prefix to Infix Expression Infix, Postfix and Prefix Notations/Expressions Valid Multiple Parentheses Valid Brackets – Part 2 | Stack Method Given two strings validate the output string Generate all the strings of length n from 0 to k-1. Find Largest and Smallest word in a given String Reverse the given String using Stack Check if two Strings are equal without using built-in function - Java Remove Vowels from a given String Find number of Distinct Permutations of a String 1 2