题目
- // luogu-judger-enable-o2
- #include<cstdio>
- #include<algorithm>
- #include<iostream>
- using namespace std;
- struct node
- {
- int tree[100100];
- int num;
- int lowbit(int x)
- {
- return x&(-x);
- }
- void updata(int x,int i)
- {
- while(i<=num)
- {
- tree[i]+=x;
- i+=lowbit(i);
- }
- }
- int sum(int i)
- {
- int ans=0;
- while(i>0)
- {
- ans+=tree[i];
- i-=lowbit(i);
- }
- return ans;
- }
- int check(int l,int r)
- {
- return sum(r)-sum(l-1);
- }
- };
- node bit;
- int main()
- {
- int n,m;
- scanf("%d%d",&n,&m);
- bit.num=n;
- int a,b;
- for(int i=1;i<=n;i++)
- {
- scanf("%d%d",&a,&b);
- bit.updata(b,a);
- }
- int ans=0;
- for(int i=1;i+m-1<=n;i++)
- ans=max(ans,bit.check(i,i+m-1));
- printf("%d",ans);
- }
来源: http://www.bubuko.com/infodetail-2521489.html