if(tree[index].lazy)
{
	tree[index*2].lazy+=tree[index].lazy;
	tree[index*2+1].lazy+=tree[index].lazy;
	tree[index*2].val+=(r-l+1-(r-l+1)/2)*tree[index].lazy;
	tree[index*2+1].val+=(r-l+1)/2*tree[index].lazy;
	tree[index].lazy=0;
}
if(left<=l&&r<=right)
{
	tree[index].lazy+=val;
	tree[index].val+=(r-l+1)*val;
	return ;
}