Compilare: user.cpp: In function ‘int main()’: user.cpp:65:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0; k < pos1[p].size(); k++) dpv[pos1[p][k]]--; ^ user.cpp:68:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (currentAnswer.size() > ans) continue; ^ user.cpp:81:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (currentAnswer.size() < ans) ans = currentAnswer.size(), answer = currentAnswer; else ^ user.cpp:82:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (currentAnswer.size() == ans) answer = min(answer, currentAnswer); ^ user.cpp:54:13: warning: unused variable ‘currentAns’ [-Wunused-variable] int currentAns = 0; ^ user.cpp:21:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("paznici.in", "r", stdin); ^ user.cpp:22:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("paznici.out", "w", stdout); ^ user.cpp:24:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d ", &n, &m); ^ user.cpp:26:48: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] for (int i = 1; i <= n; i++) gets(s[i] + 1); ^ In file included from /usr/include/stdio.h:934:0, from user.cpp:1: In function ‘char* gets(char*)’, inlined from ‘int main()’ at user.cpp:26:48: /usr/include/i386-linux-gnu/bits/stdio2.h:230:28: warning: call to ‘__gets_warn’ declared with attribute warning: please use fgets or getline instead, gets can't specify buffer size [enabled by default] return __gets_warn (__str); ^ /tmp/ccqDA7lM.o: In function `main': user.cpp:(.text.startup+0x84): warning: the `gets' function is dangerous and should not be used.