摘要：
Find Peak ElementA peak element is an element that is greater than its neighbors.Given an input array wherenum[i] ≠ num[i+1], find a peak element and ... 阅读全文
摘要：
4SumGiven an arraySofnintegers, are there elementsa,b,c, anddinSsuch thata+b+c+d= target? Find all unique quadruplets in the array which gives the sum... 阅读全文