POJ3468 区间加，区间求和 线段树模板

好久没写线段树了，手有点生。。。更新的时候居然忘了更新sum集。。。最近要多练练线段树了。。。

#include 
#include 
#include 
#include 
#include 
using namespace std;

const int maxn = 100005;
typedef long long ll;

ll addv[maxn<<2];
ll sumv[maxn<<2];
ll a[maxn];
int n,q;
int x1,x2;

ll init(int v,int l,int r)
{
	if(l==r)
	{
		return sumv[v] = a[l];
	}
	int mid = (l+r)>>1;
	int chl = 2*v+1;
	int chr = chl+1;
	return sumv[v] = init(chl,l,mid) + init(chr,mid+1,r);
	
}



void add(int v,int l,int r,ll val)
{
	if(l>x2 || r=r)
	{
		addv[v] += val;
		sumv[v] += val * (r-l+1);
		return;
	}
	int mid = (l+r)>>1;
	int chl = v*2+1;
	int chr = chl + 1;
	if(mid>=x1)
		add(chl,l,mid,val);
	if(midx2 || r=r)
	{
		return sumv[v] + d * (r-l+1); 
	}
	int mid = (l+r)>>1;
	int chl = v*2+1;
	int chr = chl + 1;
	return query(chl,l,mid,addv[v]+d) + query(chr,mid+1,r,addv[v]+d);
}

int main()
{
	int i,j;
	scanf("%d%d",&n,&q);
	for(i=0;i