二维树状数组区间修改+区间查询模版

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
int i,j,k,n,m,p,q,t1[2005][2005],t2[2005][2005],t3[2005][2005],t4[2005][2005];
long long int x1,y,x2,y2;
long long int lowbit(long long int p)
{
    return p & (-p);
}
void add(long long x,long long y,long long z)//单点修改 
{
    for(int X = x;X <= n;X+= lowbit(X))
    {
        for(int Y = y;Y <= m;Y += lowbit(Y))
        {
            t1[X][Y] += z;
            t2[X][Y] += z * x;
            t3[X][Y] += z * y;
            t4[X][Y] += z * x * y;
        }
    }
}
void qiuhe(long long int x1,long long int y,long long int x2,long long int y2,int z)//区间修改 
{
    add(x1,y,z);
    add(x1,y2 + 1,-z);
    add(x2 + 1,y,-z);
    add(x2 + 1,y2 + 1,z);
}
long long int ask(long long int x,long long int y)//求前缀和 
{
    long long int res = 0;
    for(i = x;i > 0;i -= lowbit(i))
    {
        for(j = y;j > 0;j -= lowbit(j))
        {
            res  += (x + 1) * (y + 1) * t1[i][j] - (y + 1) * t2[i][j] - (x + 1) * t3[i][j] + t4[i][j]; 
        }
    }
    return res;
 } 
long long int daan(long long int x1,long long int y,long long int x2,long long int y2)//求解 
{
    return ask(x2,y2) - ask(x1-1,y2) - ask(x2,y-1) + ask(x1 - 1,y - 1);
}
int main()
{
    scanf("%d %d %d %d",&n,&m,&p,&q);
    for(i = 1;i <= p;i++) 
    {
        scanf("%d %d %d %d",&x1,&y,&x2,&y2);
        qiuhe(x1,y,x2,y2,1);
    }
    for(int t = 1;t <= q;t++)
    {
        scanf("%d %d %d %d",&x1,&y,&x2,&y2);
        printf("%lld
",daan(x1,y,x2,y2));
    }
    return 0;
}