Compilare: user.cpp: In function ‘int main()’: user.cpp:37:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<has[lista].size(); i++) ^ user.cpp:56:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<has[i].size(); j++) ^ user.cpp:20:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("litere2.in", "r", stdin); ^ user.cpp:21:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("litere2.out", "w", stdout); ^ user.cpp:22:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(sir); ^ /tmp/ccDqA8bz.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.