Compilare: user.cpp: In function ‘int main()’: user.cpp:107:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < val.size(); i++) ^ user.cpp:96:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cumpanit.in", "r", stdin); ^ user.cpp:97:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cumpanit.out", "w", stdout); ^ user.cpp:99:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld", &a, &b); ^