#include<bits/stdc++.h> using namespace std; int yzh(int n) { int s=0; for(int i=2;i<=n-1;i++) { if(n%i==0) { s+=i; } } return s; } int main() { int n; cin>>n; for(int i=1;i<=n;i++) { for(int j=1;j<=n;j++) { if(yzh(i)==j&&yzh(j)==i) { cout<<i<<" "<<j<<endl; } } } return 0; } /************************************************************** Problem: 1140 User: wangyuxin Language: C++ Result: Accepted Time:33 ms Memory:2072 kb ****************************************************************/