#include <bits/stdc++.h>
using namespace std;

int a,b,c;

int main(){
    cin >> a >> b >> c;
    cout << (a + b) * c;//×要写成*
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int a,b,c;
    cin>>a>>b>>c;
    cout<<(a+b)*c<<endl;
    return 0;
}

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

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