include iostream include vector include algorithm include cstdio inclu

#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <string>
#include <cmath>
#include <iomanip>
#include <queue>

using namespace std;

int mat[3][3] = {0};

int main() {
  //freopen("input.txt", "r", stdin);
  //freopen("output.txt", "w", stdout);
  
  for (int i = 0; i < 3; i++)
    for (int j = 0; j < 3; j++)
      cin >> mat[i][j];

  long long a = 0;

  a += mat[0][0] * (mat[1][1] * mat[2][2] - mat[1][2] * mat[2][1]);
  a -= mat[0][1] * (mat[1][0] * mat[2][2] - mat[1][2] * mat[2][0]);
  a += mat[0][2] * (mat[1][0] * mat[2][1] - mat[1][1] * mat[2][0]);

  cout << a << endl;

  return 0;
}