Compilare: user.cpp: In function ‘int bs(std::vector<int>, int)’: user.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(st==a.size()) return -1; ^ user.cpp: In function ‘int main()’: user.cpp:57:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("potrivire.in", "r", stdin); ^ user.cpp:58:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("potrivire.out", "w", stdout); ^ user.cpp:60:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &n, &m); ^ user.cpp:61:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a+1); gets(b+1); ^ user.cpp:61:25: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a+1); gets(b+1); ^ /tmp/ccUpavGa.o: In function `main': user.cpp:(.text.startup+0x72): warning: the `gets' function is dangerous and should not be used.