# Status Problem Level Completes Likes 1 Depth-First Search (DFS) in 2D Matrix/2D-Array - Iterative Solution Beginner % 0 2 Print Stack in reverse order. Beginner % 0 3 Sort a given stack - Using Recursion Hard % 1 4 Evaluation of Prefix Expressions (Polish Notation) | Set 2 Medium % 0 5 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Medium % 0 6 Smallest Number after Removing K digits Hard % 0 7 Reverse a Stack using recursion - In Place (Without using extra memory) Hard % 1 8 Convert Prefix to Postfix Expression Medium % 0 9 Sort a given stack - Using Temporary Stack Medium % 0 10 Convert Postfix to Infix Expression Medium % 0 11 Convert Infix to Prefix Expression Medium % 0 12 Convert Infix to Postfix Expression Medium % 0 13 Evaluation of Infix expressions Medium % 0 14 Stack Java Class - Explained Beginner % 0 15 Convert Prefix to Infix Expression Medium % 0 16 Infix, Postfix and Prefix Notations/Expressions Beginner % 0 17 Valid Multiple Parentheses Medium % 1 18 Stack Data Structure – Introduction and Implementation Beginner % 0 19 Reverse the given String using Stack Beginner % 0 20 Implement Stack Using Linked List Beginner % 0 21 Implement Queue Using Stacks Medium % 0 Depth-First Search (DFS) in 2D Matrix/2D-Array - Iterative Solution Print Stack in reverse order. Sort a given stack - Using Recursion Evaluation of Prefix Expressions (Polish Notation) | Set 2 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Smallest Number after Removing K digits Reverse a Stack using recursion - In Place (Without using extra memory) Convert Prefix to Postfix Expression Sort a given stack - Using Temporary Stack Convert Postfix to Infix Expression Convert Infix to Prefix Expression Convert Infix to Postfix Expression Evaluation of Infix expressions Stack Java Class - Explained Convert Prefix to Infix Expression Infix, Postfix and Prefix Notations/Expressions Valid Multiple Parentheses Stack Data Structure – Introduction and Implementation Reverse the given String using Stack Implement Stack Using Linked List Implement Queue Using Stacks 1
