感觉不太正确却又AC的自解：
#include<bits/stdc++.h>
using namespace std;
int main(){
int x,n;
int zhou,yu;
int sum1=0,sum2=0;//天数
cin>>x>>n;
zhou = n/7;
yu = n-zhou*7;
sum1 = zhou*5;
if(yu == 0)
sum2 = 0;
else if(x+yu<=6)
sum2 = yu;//不是yu+1;
else if(x+yu==7&&x!=6&&x!=7)
sum2 = yu-(x-1);//sum2 = yu;
else if(x+yu==7&&x==6)/
sum2 = 0;//
else if(x+yu==8&&(x==6||x==7))//x+yu>=8
sum2 = 0;
else if(x==6&&(x+yu>=9))
sum2 = yu-2;
else if(x==7&&(x+yu>=10))
sum2 = yu-1;
else
sum2 = yu-2;
// cout<<"yu="<<yu<<" sum1="<<sum1<<" sum2="<<sum2<<endl;
cout<<(sum1+sum2)*250;
return 0;
}
// 7 543543 zheng97061250 97062750 yu=0
//#5 1 10 20000 2250 yu=3
//#8 4 12345 2204250 2204500 yu=4
//#3 7 10 1750 1500
