新手求哪错了

#include<iostream>
using namespace std;
int money(int i){
    int a,b,c;
    c=0;
    for(b=1;b<=a;b++){
                      while(a%b==0)
                      c++;
                      if(c==2)
                      return a;
                      else
                      break;
                      }
                      }
int main(){
        int i;
        cout<<"请输入一个数";
        cin>>i;
        if(money(i))
        cout<<"是质数";
        system("pause");
        return 0;
        }