Compilare: user.cpp: In function ‘int main()’: user.cpp:40:11: warning: unused variable ‘x’ [-Wunused-variable] int i,x,y,M,key; ^ user.cpp:40:13: warning: unused variable ‘y’ [-Wunused-variable] int i,x,y,M,key; ^ user.cpp:40:17: warning: unused variable ‘key’ [-Wunused-variable] int i,x,y,M,key; ^ user.cpp:41:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxq.in","r",stdin); ^ user.cpp:42:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxq.out","w",stdout); ^ user.cpp:43:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&N); ^ user.cpp:45:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i]),Up(1,N,i,a[i],1); ^ user.cpp:46:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&M); ^