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(luogu 3374)
单点修改,区间查询
模板如下:
#include <bits/stdc++.h>
#define ll long long
#define N 500005
using namespace std;
int a[N],c[N];
int n,m;
int lowbit(int x)
{
return x & -x;
}
void add(int x,int w)
{
while(x<=n)
{
c[x]+=w;
x+=lowbit(x);
}
}
ll sum(int x)
{
ll ret=0;
while(x)
{
ret+=c[x];
x-=lowbit(x);
}
return ret;
}
int main()
{
scanf("%d%d",&n,&m);
for(int i = 1;i <= n;i++)
{
scanf("%d",&a[i]);
add(i,a[i]);
}
for(int i = 1;i <= m;i++)
{
int q,w,e;
scanf("%d%d%d",&q,&w,&e);
if(q==1)
{
add(w,e);
}else if(q==2)
{
printf("%lld\n",sum(e)-sum(w-1));
}
}
return 0 ;
}