Compilare: user.cpp: In function ‘int main(int, const char**)’: user.cpp:53:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz == d.size()) ^ user.cpp:61:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < d.size(); ++i) ^ user.cpp:71:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < d.size(); ++i) ^ user.cpp:20:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("exp.in", "r", stdin); ^ user.cpp:21:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("exp.out", "w", stdout); ^ user.cpp:25:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd %d", &m, &n); ^ user.cpp:43:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd", &x); ^