#include<bits/stdc++.h>
using namespace std;
const int maxn=2e5+6;
#define ll long long
#define il long long

void solve()
{
	ll a1,a2,a3,a4;
	cin>>a1>>a2>>a3>>a4;
	cout<<a2*a4<<endl;
	
}
int  main(){
	ios::sync_with_stdio(false);	
	int t=1;
	//cin>>t;
	//ll res=1;
	//for(int i=1;i<=13;i++)res*=i;
	//cout<<res<<'\n';
	while(t--)solve();
	return 0;
}