Compilare: user.cpp: In function ‘int main()’: user.cpp:31:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < v.size(); ++i) ^ user.cpp:38:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (ways = 1 , mars = 0 , i = 0; i < v.size(); ++i) ^ user.cpp:16:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ben.in","r",stdin); ^ user.cpp:17:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ben.out","w",stdout); ^ user.cpp:19:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:23:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &left, &right); ^