日拱一卒 功不唐捐

摘要： https://www.luogu.org/problem/show?pid=2564 题目描述 小西有一条很长的彩带，彩带上挂着各式各样的彩珠。已知彩珠有N个，分为K种。简单的说，可以将彩带考虑为x轴，每一个彩珠有一个对应的坐标(即位置)。某些坐标上可以没有彩珠，但多个彩珠也可以出现在同一个位置上 阅读全文

摘要： https://www.luogu.org/problem/show?pid=3029 题目描述 Farmer John has hired a professional photographer to take a picture of some of his cows. Since FJ's c 阅读全文