Compilare: user.cpp: In function ‘void _fill(short int, short int, short int)’: user.cpp:25:7: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if( b[i][j] == -1 && cond(i, j) ) ^ user.cpp: In function ‘int main()’: user.cpp:33:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.in" , "r", stdin ); ^ user.cpp:34:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxa.out", "w", stdout); ^ user.cpp:35:68: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d%d", &N, &M, &beg.x, &beg.y, &fin.x, &fin.y ); ^ user.cpp:38:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]) , b[i][j]= -1; ^