1.Two Sum II
2.triangle-count
for(i=0到n)枚举一条边,找j<i,k<j的和大于所对应的边。
3.给n个数组要求其中k大的元素
还可以两两归并
4.Kth Largest Element
5.nuts-bolts-problem
灌水类题目
1. Trapping Rain Water
2.Container With Most Water
前向型或者追击型(窗口类,快慢类)
1.Minimum Size Subarray Sum
2.Longest Substring Without Repeating Characters
3. Minimum Window Substring
4. Longest Substring with at Most k Distinct Characters