Compilare: user.cpp: In function ‘void solve2(int)’: user.cpp:11:12: warning: unused variable ‘j’ [-Wunused-variable] int b, j, flag, newconfig; ^ user.cpp: In function ‘void solve()’: user.cpp:35:23: warning: unused variable ‘j’ [-Wunused-variable] int config, b, i, j; ^ user.cpp: In function ‘int main()’: user.cpp:53:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("coins.in", "r", stdin); ^ user.cpp:54:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("coins.out", "w", stdout); ^ user.cpp:57:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &n); ^ user.cpp:62:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &x); ^