Compilare: user.cpp: In function ‘int main()’: user.cpp:36:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(a[i][j] <= per) ^ user.cpp:13:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zmeu.in", "r", stdin); ^ user.cpp:14:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zmeu.out", "w", stdout); ^