#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn = 2e5+5;
#define _time_      1.0 * clock() / CLOCKS_PER_SEC
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t;t=1;
    while(t--){
        ll n;cin>>n;
        ll h,w;cin>>h>>w;
        ll q= n/2;
        ll r = n - n/2;
        ll ans = q*r*(h+w-2);
        cout<<ans<<" ";
        
    }
}