Compilare: user.c:33:5: warning: first argument of ‘main’ should be ‘int’ [-Wmain] int main(char *argv[]){ ^ user.c:33:5: warning: ‘main’ takes only zero or two arguments [-Wmain] user.c: In function ‘main’: user.c:37:8: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &N, &M); ^ user.c:48:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d", &a[i][j]); ^