//#include "stdafx.h"//If the vc++6.0, with this line.
#include <iostream>
using namespace std;
int main(int argc,char *argv[]){
int n;
cout << "Please enter n(int 19<n<10000001)...\nn=";
if(!(cin >> n) || n<21 || n>10000000){
cout << "Input error, exit...\n";
return 0;
}
for(int k=n>>1,sum=0,i=2;i<=k;i++)
if(n%i==0)
sum+=i;
cout << "The result is " << sum << " when n==" << n << endl;
return 0;
}
运行样例: