Compilare: user.cpp: In function ‘int main()’: user.cpp:36:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(l=0; l<h.size(); ++l)if(h[l].first==k){h[l].second++;break;} ^ user.cpp:37:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(l==h.size()){h.push_back(make_pair(k, 1));} ^ user.cpp:29:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("avarcolaci.in", "r", stdin); ^ user.cpp:30:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("avarcolaci.out", "w", stdout); ^ user.cpp:31:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:33:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:35:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &k); ^