Compilare: user.cpp: In function ‘int main()’: user.cpp:42:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] freq[s[cr+1]]=1; ^ user.cpp:53:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<same.size(); ++i) ^ user.cpp:62:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<dif.size(); ++i) ^ user.cpp:80:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<vec[i].size(); ++j) ^ user.cpp:27:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pmk.in", "r", stdin); ^ user.cpp:28:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pmk.out", "w", stdout); ^ user.cpp:30:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:32:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^