임의로 주어지는 배열중 두개의 합이 target 일치하는 "index" 를 찾아라.
괄호의 짝이 맞는지 확인하는 문제.Runtime: 72 ms, faster than 95.80% of JavaScript online submissions for Valid Parentheses.Memory Usage: 38.9 MB, less than 53.24% o
Runtime: 140 ms, faster than 53.41% of JavaScript online submissions for Add Two Numbers.Memory Usage: 43.9 MB, less than 85.30% of JavaScript online