Compilare: user.cpp: In function ‘int main()’: user.cpp:62:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("xp.in", "r", stdin); ^ user.cpp:63:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("xp.out", "w", stdout); ^ user.cpp:65:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d", &N, &A1, &B1, &P, &Q); ^