Compilare: user.cpp: In function ‘bool liber(int, int, int)’: user.cpp:14:121: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] if (a[i][j] == 0 && a[i][j - 1] == 0 && a[i - 1][j] == 0 && a[i - 1][j - 1] == 0 && conf & (1 << j) && conf & (1 << j - 1)) ^ user.cpp: In function ‘int main()’: user.cpp:50:89: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] dp[i][j][conf] = max(dp[i][j][conf], dp[i][j - 2][conf ^ (1 << j) ^ (1 << j - 1)] + 1); ^ user.cpp:48:12: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (j > 0 && liber(i, j, conf)) ^ user.cpp:20:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pavare.in", "r", stdin); ^ user.cpp:21:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pavare.out", "w", stdout); ^ user.cpp:24:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:26:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &k); ^ user.cpp:29:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^