# Status Problem video Level Completes Likes 420 Number's Complement - 2 Approaches Medium % 1 419 Print all subsets of an array with a sum equal to zero Medium % 0 416 Evaluation of Prefix Expressions (Polish Notation) | Set 2 Medium % 0 414 Breadth-First Search in Disconnected Graph Medium % 0 413 ZigZag OR Diagonal traversal in 2d array/Matrix using queue Medium % 0 410 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Medium % 0 409 Minimum Boats Required to rescue people Medium % 0 408 Number of Islands Medium % 1 407 Integer Replacement Problem Medium % 0 406 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 2 Medium % 0 405 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 1 Medium % 0 402 Check if Arithmetic Expression contains duplicate parenthesis Medium % 0 401 Introduction to Bipartite Graphs OR Bigraphs Medium % 0 396 Optimizing Test Execution: Managing Test Dependencies for Sequential Order Medium % 0 395 Implement Graph Using Map or dictionary Medium % 0 391 Check if given an edge is a bridge in the graph Medium % 0 390 Convert Prefix to Postfix Expression Medium % 0 388 Sort a given stack - Using Temporary Stack Medium % 0 387 Convert Postfix to Prefix Expression Medium % 0 386 Convert Integer to Roman Medium % 0 Number's Complement - 2 Approaches Print all subsets of an array with a sum equal to zero Evaluation of Prefix Expressions (Polish Notation) | Set 2 Breadth-First Search in Disconnected Graph ZigZag OR Diagonal traversal in 2d array/Matrix using queue Evaluation of Prefix Expressions (Polish Notation) | Set 1 Minimum Boats Required to rescue people Number of Islands Integer Replacement Problem Evaluation of Postfix Expressions (Polish Postfix notation) | Set 2 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 1 Check if Arithmetic Expression contains duplicate parenthesis Introduction to Bipartite Graphs OR Bigraphs Optimizing Test Execution: Managing Test Dependencies for Sequential Order Implement Graph Using Map or dictionary Check if given an edge is a bridge in the graph Convert Prefix to Postfix Expression Sort a given stack - Using Temporary Stack Convert Postfix to Prefix Expression Convert Integer to Roman 1 2 3 4 5 6 7 8 9 10 11 12