Compilare: user.cpp: In function ‘int main()’: user.cpp:74:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); ++i) ^ user.cpp:66:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dir.in", "r", stdin); ^ user.cpp:69:44: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1), n = strlen(s + 1), ind = 1; ^ /tmp/ccdttLyT.o: In function `main': user.cpp:(.text.startup+0x67): warning: the `gets' function is dangerous and should not be used.