Compilare: user.cpp: In function ‘int main()’: user.cpp:12:17: warning: unused variable ‘ins’ [-Wunused-variable] ll inv = 0, ins; ^ user.cpp:13:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("inversmodular.in", "r", stdin); ^ user.cpp:14:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("inversmodular.out", "w", stdout); ^ user.cpp:15:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &A, &N); ^