Compilare: user.cpp: In function ‘int main()’: user.cpp:77:11: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] k=1<<n-1; ^ user.cpp:60:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("avd.in","r",stdin); ^ user.cpp:61:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("avd.out","w",stdout); ^ user.cpp:62:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%ld",&teste); ^ user.cpp:65:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%ld",&n); ^ user.cpp:73:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%ld%ld",&x,&y); ^