#include<bits/stdc++.h>
#define int long long
using namespace std;
/*
1 	2	 3	 4
12  13  14	 5
11  16 	15	 6
10	9    8 	 7
*/
/*
4 1 4
4 2 4
*/
int x,y;
int a[101][101];
signed main(){
	int n, i, j;
    cin >> n >> i >> j;
    int s = min({i, j, n - i + 1, n - j + 1});
    int start = (2 * s - 2) * (2 * n - 2 * s + 2) + 1;
    int len = n - 2 * s + 1;
    if (i == s) {
        cout << start + j - s;
    } else if (j == n - s + 1) {
        cout << start + len - 1 + i - s;
    } else if (i == n - s + 1) {
        cout << start + 2 * (len - 1) + (n - s + 1) - j;
    } else {
        cout << start + 3 * (len - 1) + (n - s + 1) - i ;
    }
	return 0;
}
/**************************************************************
	Problem: 2332
	User: chenyongtian
	Language: C++
	Result: Runtime Error
****************************************************************/