codeforces 234E Champions' League

本文介绍了一个针对 CodeForces 平台上的 234E 题目的解决方案。该题涉及随机数生成及队伍分组算法。通过使用 C++ 实现,文章详细展示了如何根据积分将队伍分为四个等级,并利用特定规则进行随机分组。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

传送门:http://codeforces.com/problemset/problem/234/E
题目大意:(注意要用文件)有n个队伍,每个队伍都有一个积分,按照积分高低顺序列出4个等级(每个等级n/4个,所以n一定是4的倍数),然后x,a,b,c这4个数就是一个随机数产生器,按照x=(x*a+b)mod c的规则来生成随机数,每生成一个随机数,便把这一个等级里的这个随机数所指向的队伍归类到group a里(或者是group b),当4个等级刷完一遍后,然后再刷另一个队伍。(p.s.我知道我解释得很丑,将就着看吧。)
ac程序

//
//  main.cpp
//  champions
//
//  Created by zhangdenny on 16/7/14.
//  Copyright (c) 2016年 Kirito. All rights reserved.
//

#include  <functional>
#include  <algorithm>
#include  <exception>
#include  <stdexcept>
#include  <streambuf>
#include  <iterator>
#include  <string.h>
#include  <stdlib.h>
#include  <typeinfo>
#include  <valarray>
#include  <iostream>
#include  <sstream>
#include  <istream>
#include  <stdio.h>
#include  <climits>
#include  <clocale>
#include  <complex>
#include  <csetjmp>
#include  <csignal>
#include  <cstdarg>
#include  <cstddef>
#include  <ctype.h>
#include  <cassert>
#include  <cstdlib>
#include  <utility>
#include  <cstring>
#include  <numeric>
#include  <ostream>
#include  <cwctype>
#include  <fstream>
#include  <iomanip>
#include  <math.h>
#include  <bitset>
#include  <cctype>
#include  <string>
#include  <vector>
#include  <limits>
#include  <locale>
#include  <memory>
#include  <cerrno>
#include  <iosfwd>
#include  <cfloat>
#include  <cstdio>
#include  <cwchar>
#include  <cmath>
#include  <ctime>
#include  <deque>
#include  <queue>
#include  <stack>
#include  <list>
#include  <ios>
#include  <map>
#include  <set>
#include  <new>
#define ft first
#define sd second
#define np next_permutation
#define ll long long
#define pb push_back
using namespace std;
int n,x,a,b,c;
bool flag[105];
vector<int> ans[105];
pair<int,string> m[105];
int sui()
{
    x*=a;
    x+=b;
    if(x<=c)
        x=x;
    else
        x=x%c;
    return x;
}
int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    cin>>n;
    cin>>x>>a>>b>>c;
    for (int i=1;i<=n;i++)
    {
        cin>>m[i].sd;
        cin>>m[i].ft;
    }
    sort(m+1,m+n+1);
    n/=4;
    for (int i=1;i<=n;i++)
    {
        for (int j=4;j>=1;j--)
        {
            int test=sui()%(n-i+1)+1;
            int test1=j*n+1;
            while (test>0)
            {
                test1--;
                if (!flag[test1])
                    test--;
            }
            flag[test1]=1;
            ans[i].push_back(test1);
        }
        cout<<"Group "<<char('A'+i-1)<<":"<<endl;
        for (int j=0;j<4;j++)
            cout<<m[ans[i][j]].sd<<endl;
    }
    return 0;
}
### Codeforces 887E Problem Solution and Discussion The problem **887E - The Great Game** on Codeforces involves a strategic game between two players who take turns to perform operations under specific rules. To tackle this challenge effectively, understanding both dynamic programming (DP) techniques and bitwise manipulation is crucial. #### Dynamic Programming Approach One effective method to approach this problem utilizes DP with memoization. By defining `dp[i][j]` as the optimal result when starting from state `(i,j)` where `i` represents current position and `j` indicates some status flag related to previous moves: ```cpp #include <bits/stdc++.h> using namespace std; const int MAXN = ...; // Define based on constraints int dp[MAXN][2]; // Function to calculate minimum steps using top-down DP int minSteps(int pos, bool prevMoveType) { if (pos >= N) return 0; if (dp[pos][prevMoveType] != -1) return dp[pos][prevMoveType]; int res = INT_MAX; // Try all possible next positions and update 'res' for (...) { /* Logic here */ } dp[pos][prevMoveType] = res; return res; } ``` This code snippet outlines how one might structure a solution involving recursive calls combined with caching results through an array named `dp`. #### Bitwise Operations Insight Another critical aspect lies within efficiently handling large integers via bitwise operators instead of arithmetic ones whenever applicable. This optimization can significantly reduce computation time especially given tight limits often found in competitive coding challenges like those hosted by platforms such as Codeforces[^1]. For detailed discussions about similar problems or more insights into solving strategies specifically tailored towards contest preparation, visiting forums dedicated to algorithmic contests would be beneficial. Websites associated directly with Codeforces offer rich resources including editorials written after each round which provide comprehensive explanations alongside alternative approaches taken by successful contestants during live events. --related questions-- 1. What are common pitfalls encountered while implementing dynamic programming solutions? 2. How does bit manipulation improve performance in algorithms dealing with integer values? 3. Can you recommend any online communities focused on discussing competitive programming tactics? 4. Are there particular patterns that frequently appear across different levels of difficulty within Codeforces contests?
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值