[题目链接]:click here~~ [题目大意] 一组题目的数目(n<=15),每一个题目有对应的难度,问你选择一定的题目(大于r个且小于l个)且选择后的题目里最小难度与最大难度差不小于x,求选择方案数. [解题思路]: DFS+回溯. 先发一发比較拙的代码: #include <bits/stdc++.h> using namespace std; const int N=1e5+10; int num[N],mum[N]; int n,m,q,t,l,r; int top,ans…

B. Preparing Olympiad You have n problems. You have estimated the difficulty of the i-th one as integer ci. Now you want to prepare a problemset for a contest, using some of the problems you've made. A problemset for the contest must consist of at le…

B. Preparing Olympiad Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/B Description You have n problems. You have estimated the difficulty of the i-th one as integer ci. Now you want to prepare a problemset for…

Preparing Olympiad time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You have n problems. You have estimated the difficulty of the i-th one as integer ci. Now you want to prepare a problemse…

Generalized Palindromic Number Time Limit: 2 Seconds      Memory Limit: 65536 KB A number that will be the same when it is written forwards or backwards is known as a palindromic number. For example, 1234321 is a palindromic number. We call a number …

题目链接:A. Sereja and Swaps 题意:给定一个序列,能够交换k次,问交换完后的子序列最大值的最大值是多少 思路:暴力枚举每一个区间,然后每一个区间[l,r]之内的值先存在优先队列内,然后找区间外假设有更大的值就替换掉. 求出每一个区间的最大值,最后记录下全部区间的最大值 代码: By lab104_yifan, contest: Codeforces Round #243 (Div. 2), problem: (C) Sereja and Swaps, Accepted, #…

就暴力枚举所有起点和终点就行了. 我做这题时想的太多了,最简单的暴力枚举起始点却没想到...应该先想最简单的方法,层层深入. #include<iostream> #include<cstdio> #include<cstdlib> #include<cstring> #include<cmath> #include<map> #include<set> #include<vector> #include<…

题意:给定 13 张麻将牌,问你是不是“听”牌,如果是输出“听”哪张. 析:这个题,很明显的暴力,就是在原来的基础上再放上一张牌,看看是不是能胡,想法很简单,也比较好实现,结果就是TLE,一直TLE,这不科学啊... 好不容易写出来的,竟然TLE...心痛.就是先确定一个将牌,然后再对刻子和顺子进行分析,其实是要剪枝的,就是在如果有1张或者两张牌,而你又不能构成刻子的时候,就要返回false,因为这就已经没解了. 这一个剪枝,就AC了. 代码如下: #pragma comment(linker,…

A. time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Rock... Paper! After Karen have found the deterministic winning (losing?) strategy for rock-paper-scissors, her brother, Koyomi, comes up…

A. Bear and Big Brother time limit per test:1 second memory limit per test:256 megabytes input:standard input output:standard output Bear Limak wants to become the largest of bears, or at least to become larger than his brother Bob. Right now, Limak…