loj6277

题解：

树状数组模板提

代码：

#include<bits/stdc++.h>
using namespace std;
const int N=50005;
int num[N],n,a[N],l,r,c,opt;
void insert(int x,int y)
{
    for (;x<=n;x+=x&-x)num[x]+=y;
}
int find(int x)
{
    int ans=0;
    for (;x;x-=x&-x)ans+=num[x];
    return ans;
}
int main()
{
    scanf("%d",&n);
    for (int i=1;i<=n;i++)scanf("%d",&a[i]),insert(i,a[i]-a[i-1]);
    for (int i=1;i<=n;i++)
     {
         scanf("%d%d%d%d",&opt,&l,&r,&c);
         if (opt==1)printf("%d
",find(r));
         else insert(l,c),insert(r+1,-c);
     }
}