Compilare: user.cpp: In function ‘int main()’: user.cpp:11:9: warning: unused variable ‘k’ [-Wunused-variable] int k=0,n,x,i; ^ user.cpp:9:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("patrate6.in","r",stdin); ^ user.cpp:10:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("patrate6.out","w",stdout); ^ user.cpp:12:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:15:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^