Compilare: user.cpp: In function ‘bool match(int)’: user.cpp:15:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < l[x].size(); ++i) ~~^~~~~~~~~~~~~ user.cpp:22:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < l[x].size(); ++i) ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:61:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < l[i].size(); ++j) { ~~^~~~~~~~~~~~~ user.cpp:35:35: 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:36:37: 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:39:22: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s, MAX, stdin); ^ user.cpp:41:23: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s, MAX, stdin); ^