text: #include "structures.h"
  
  // Checks if a number n can go in a coordinate cell (i; j).
  int verify_cell(int grid[9][9], int n, int i, int j);
  
  // Checks all the possibilities of all the cells in the game.
  void verif_possibilites(int grid[9][9], nb grid_poss[9][9]);
  
  // Checks if the game is finished, therefore if all the cells are filled.
  void verif_finish(int grid[9][9], int *finished);
  
  //  checks if a grid is solvable
  int verif_impossible(int grid[9][9]);
  
  // checks if a grid is valid
  int verif_valid(int grid[9][9], int mistakes[9][9]);
  