Compilare: user.cpp: In function ‘int find_next(int)’: user.cpp:35:7: warning: unused variable ‘ok’ [-Wunused-variable] bool ok = false; ^ user.cpp: In function ‘int main()’: user.cpp:76:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<answer[i].size(); j++) ^ user.cpp:45:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("patrate5.in", "r", stdin); ^ user.cpp:46:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("patrate5.out", "w", stdout); ^ user.cpp:48:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^