1336 : Matrix Sum (hihocoder)

题目链接: 点击打开链接

二维树状数组,百度一大堆,我只是存代码的

#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<string.h>
#include<string>


using namespace std;
typedef long long int LL;
const int INF=2e9+1e8;
const int MM=1010;
const LL MOD=1e9+7;


LL n,m,bitnum[MM][MM];

LL lowbit(LL x)
{
    return x&(-x);
}
void add(LL xx,LL yy,LL num)
{
    for(int x=xx;x<=n+1;x+=lowbit(x))
    {
        for(int y=yy;y<=n+1;y+=lowbit(y))
        {
            bitnum[x][y]+=num;
        }
    }
}
LL sum(LL l,LL r)
{
    LL ans=0;
    for(int x=l;x>0;x-=lowbit(x))
    {
        for(int y=r;y>0;y-=lowbit(y))
        {
            ans+=(bitnum[x][y])%MOD;
        }
    }
    return ans%MOD;
}
LL getsum(LL x1,LL y1,LL x2,LL y2)
{
    LL ans=sum(x2,y2)-sum(x1-1,y2)-sum(x2,y1-1)+sum(x1-1,y1-1);
    while(ans<0) ans+=MOD;
    return ans;
}

int main()
{
    memset(bitnum,0,sizeof(bitnum));
    cin>>n>>m;
    for(int i=0;i<m;i++)
    {
        char opt[10];
        LL x1,y1,x2,y2,val;
        cin>>opt;
        if(opt[0]=='A')
        {
            cin>>x1>>y1>>val;
            add(x1+1,y1+1,val);
        }
        else
        {
            cin>>x1>>y1>>x2>>y2;
            cout<<getsum(x1+1,y1+1,x2+1,y2+1)<<endl;
        }
    }
        return 0;
}


原文地址:https://www.cnblogs.com/coded-ream/p/7207955.html