#include<iostream>
using namespace std;
int fac(int n)
{  if(n>1)  return(n*fac(n-1));
    else return(n); 
    }
    
    int main()
    {  int a,b,c;
       cout<<"please input three numbers"<<endl;
       cin>>a>>b>>c;
       cout<<"a!+b!+c!= "<<fac(a)+fac(b)+fac(c) <<endl;
       system("pause");
       return 0;
        
        
        
        
        
        }