线段树_懒标记

#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cstring>
using namespace std;
const int maxn=200000*4+10;

long long sum[maxn],a[maxn],d[maxn];
int n,q;

void init()
{
freopen("4.in","r",stdin);
freopen("4.out","w",stdout);
}

void buildtree(int k,int x,int y)
{
if(x==y)
{
sum[k]=a[x];
return;
}
int t=x+((y-x)>>1);
buildtree(2*k,x,t);
buildtree(2*k+1,t+1,y);
sum[k]=sum[2*k]+sum[2*k+1];
}

void readdata()
{
memset(sum,0,sizeof(sum));
memset(d,0,sizeof(0));
scanf("%d",&n);
for(int i=1;i<=n;i++) scanf("%d",&a[i]);
scanf("%d",&q);
buildtree(1,1,n);
}

void xiugai(int k,int x,int y,int l,int r,int da)
{
if(l>y||r<x) return;
if(l<=x&&r>=y)
{
d[k]+=da;
return;
}
if(d[k])
{
d[k*2]+=d[k];
d[k*2+1]+=d[k];
d[k]=0;
}
int t=x+((y-x)>>1);
xiugai(2*k,x,t,l,r,da);
xiugai(2*k+1,t+1,y,l,r,da);
sum[k]=sum[2*k]+d[k*2]*(t-x+1)+d[k*2+1]*(y-t)+sum[2*k+1];
}

long long chakan(int k,int x,int y,int l,int r)
{
if(l>y||r<x)return 0;
if(l<=x&&r>=y)
{
return d[k]*(y-x+1)+sum[k];
}
if(d[k])
{
d[k*2]+=d[k];
d[k*2+1]+=d[k];
d[k]=0;
}
int t=x+((y-x)>>1);
long long res = chakan(2*k,x,t,l,r)+chakan(2*k+1,t+1,y,l,r);
sum[k]=sum[2*k]+d[k*2]*(t-x+1)+d[k*2+1]*(y-t)+sum[2*k+1];
return res;
}

void work()
{
for(int i=1;i<=q;i++)
{
int biaozhi,x,y,da;
scanf("%d",&biaozhi);
if(biaozhi==1)
{
scanf("%d%d%d",&x,&y,&da);
xiugai(1,1,n,x,y,da);
}
if(biaozhi==2)
{
scanf("%d%d",&x,&y);
printf("%lld\n",chakan(1,1,n,x,y));
}
}
}

int main()
{
init();
readdata();
work();
return 0;
}