Compilare: user.cpp: In function ‘int main()’: user.cpp:79:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d", &m, &n); ^ user.cpp:93:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d ", &mat[i][j]); ^ user.cpp:95:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d\n", &mat[i][n-1]); ^ user.cpp:20:12: warning: ‘bestmask’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (mask & i) { ^ user.cpp:100:6: note: ‘bestmask’ was declared here int bestmask; ^