Compilare: user.cpp: In function ‘int main()’: user.cpp:7:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cri.in", "r",stdin); ^ user.cpp:8:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cri.out", "w", stdout); ^ user.cpp:10:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &x, &y); ^ user.cpp:13:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^ user.cpp:115:63: warning: ‘mini’ may be used uninitialized in this function [-Wmaybe-uninitialized] t=s[n][m]-s[n][y-1]-s[x-1][m]+s[x-1][y-1]-mini; ^ user.cpp:29:18: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(s[i][j]-mini>t){ ^