摘要：
Givennnon-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining.Fo... 阅读全文
摘要：
Given an unsorted integer array, find the first missing positive integer.For example,Given[1,2,0]return3,and[3,4,-1,1]return2.Your algorithm should ru... 阅读全文