#include<iostream>
using namespace std;
int main(){
     int a,b,c;
     cin>>a>>b>>c;
     cout<<(a+b)*c ; 
     return 0;
 }

> > #include<iostream>
using namespace std;
int main(){
     int a,b,c;
     cin>>a>>b>>c;
     cout<<(a+b)*c ; 
     return 0;
 }