Compilare: user.cpp: In function ‘std::pair<int, int> compute(int, int, int)’: user.cpp:57:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = limit; i < A[id].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:98:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = p1; i < B.size(); i++) from[i] = cnt; ^ user.cpp:105:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (A.size() != n) A.pb(""); ^ user.cpp:78:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dist.in","r",stdin); ^ user.cpp:79:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dist.out","w",stdout); ^ user.cpp:82:18: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(aux + 1); ^ user.cpp:90:18: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(aux + 1); ^ /tmp/ccyH3JuU.o: In function `main': user.cpp:(.text.startup+0x66): warning: the `gets' function is dangerous and should not be used.