排序map、pq、stack。固定 递归 贪心 开关 二分 滑动窗口（固递贪开二滑）

摘要： ［抄题］： Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in t 阅读全文

摘要： ［抄题］： Given an array of integers and an integer k, you need to find the number of unique k-diff pairs in the array. Here a k-diff pair is defined as a 阅读全文