codeforces 234E Champions' League

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_backusing 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;}