C++ 分数代码

#include "bits/stdc++.h"
using namespace std;
int main()
{
    int a,n,res=0,combo;
    cin >> a >> n;
    for (int i = 2; i <= a; i ++ ){
        cin >> combo;
        combo=i;
        res+=max(combo,int((a%i)*max(combo,1)+0.5));
    }
    long double ans=res*(n*1.0/a);
    //ans=1501;
    cout << (n*1.0/a) << endl;
    if((n*1.0/a)<0.17) {cout << 0;exit(0);}
    if((n*1.0/a)<0.25) {cout << 120;exit(0);}
    if((n*1.0/a)<0.34) {cout << 150;exit(0);}
    if((n*1.0/a)<0.41) {cout << 190;exit(0);}
    if((n*1.0/a)<=0.52) {cout << 210;exit(0);}
    if(ans<=100) cout << max(int(ans+0.5)+100,210+int(ans*0.6+0.5));
    else if (ans<=200||(n*1.0/a)<0.17) cout << int(int(ans-100+0.5)*(0.9+((n*1.0/a)*0.05))+0.6)+200;
    else if (ans<=300||(n*1.0/a)<0.3)   cout << int(int(ans-200+0.5)*(0.81+((n*0.95/a)*0.06))+0.6)+395;
    else if (ans<=400||(n*1.0/a)<0.4) cout << int(int(ans-300+0.5)*(0.61+((n*0.95/a)*0.26))+0.6)+482;
    else if (ans<=600||(n*1.0/a)<0.45) cout << int(int(ans-400+0.5)*(0.7+((n*0.92/a)*0.22))+0.6)+576;
    else if (ans<=1000||(n*1.0/a)<0.5) cout << int(int(ans-600+0.5)*(0.5+(n*0.85/a)*0.07)+0.4)+650;
    else if (ans<=1300) cout << int(int(ans-1000+0.5)*(0.3+(n*0.85/a)*0.4)+0.2)+820;
    else if (ans<=1500) cout << int((ans-1300+0.5)*(0.4+(n*0.85/a)*0.3)+0.08)+1000;
    else cout << min(int(1020+ans*0.05),2100);
}