LeetCode Questions from LeetCode, all the code submitted LeetCode before committed The results from leetcode Add Two Numbers 182ms beat 83.77% Longest Substring Without Repeating Characters 122ms beat 99.74% Two Sum 548 ms beat 67.43% (it was 69.5% but failed to fine tune the code) Longest Palindromic Substring 176ms beat 75% Zigzag conversion 152ms 94.4% AtoI 119 ms, 97.92%