#include <bits/stdc++.h>
using namespace std;
#define Seny ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define all(v) v.begin(),v.end()
#define print(v) for(auto x : v)cout<<x<<" "
#define ll long long
#define int ll
#define endl '\n'
const int mod = 1e9 + 7;
const int N = 2e5 + 5;

void test()
{
    int n, h, v; cin >> n >> h >> v;
    int ch =  n - h;
    int cv = n - v;
    cout << max({v * h, ch * v, h * cv, ch * cv})*4;
}
signed main() {
    int t = 1;
    //cin >> t;
    while (t--)
        test();
}