Compilare: user.cpp: In function ‘void downheap(int)’: user.cpp:28:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(k*2<=cate_heap) ^ user.cpp:31:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz+1<=cate_heap and heap[poz+1].val<heap[poz].val) ^ user.cpp: In function ‘int main()’: user.cpp:45:19: warning: unused variable ‘j’ [-Wunused-variable] ull n,k,s=0,i,j,x,y; ^ user.cpp:45:21: warning: unused variable ‘x’ [-Wunused-variable] ull n,k,s=0,i,j,x,y; ^ user.cpp:45:23: warning: unused variable ‘y’ [-Wunused-variable] ull n,k,s=0,i,j,x,y; ^