二维线段树模板

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
#define ll o<<1
#define rr o<<1|1
const int maxn=1200;
const int inf=0x3f3f3f3f;
const long long inff=1e18+10;
struct nodey
{
	int ly,ry,val,maxx,minn,sum;
};
int nx,ny;// 矩阵的长和宽 
int posx[maxn],posy[maxn];//(x,y)对应的结点 
struct nodex
{
	int lx,rx;
	nodey treey[maxn<<2];
	void build_y(int o,int l,int r)//内层建树 
	{
		treey[o].ly=l;
		treey[o].ry=r;
		treey[o].maxx=0;
		treey[o].minn=inf;
		treey[o].sum=0;
		treey[o].val=0;
		if(l==r)
		{
			posy[l]=o;
			return;
		}
		int mid=(l+r)>>1;
		build_y(ll,l,mid);
		build_y(rr,mid+1,r);
	}
	int query_y(int o,int y1,int y2,int op)
	{
		if(treey[o].ly==y1&&treey[o].ry==y2)
		{
			if(op==0)
				return treey[o].maxx;
			if(op==1)
				return treey[o].minn;
			if(op==2)
				return treey[o].sum;
		}
		int mid=(treey[o].ly+treey[o].ry)>>1;
		if(y2<=mid)
		{
			return query_y(ll,y1,y2,op);
		}
		else if(y1>mid)
		{
			return query_y(rr,y1,y2,op);
		}
		else
		{
			if(op==0)
				return max(query_y(ll,y1,mid,op),query_y(rr,mid+1,y2,op));
			if(op==1)
				return min(query_y(ll,y1,mid,op),query_y(rr,mid+1,y2,op));
			if(op==2)
				return 	query_y(ll,y1,mid,op)+query_y(rr,mid+1,y2,op);
		}
	} 
};
nodex treex[maxn<<2];
void build_x(int o,int l,int r)
{
	treex[o].lx=l;
	treex[o].rx=r;
	treex[o].build_y(1,1,ny);
	if(l==r)
	{
		posx[l]=o;
		return ;
	}
	int mid=(l+r)/2;
	build_x(ll,l,mid);
	build_x(rr,mid+1,r);
}
int query_x(int o,int x1,int x2,int y1,int y2,int op)
{
	if(treex[o].lx==x1&&treex[o].rx==x2)
	{
		return treex[o].query_y(1,y1,y2,op);
	}
	int mid=(treex[o].lx+treex[o].rx)>>1;
	if(x2<=mid)
		return query_x(ll,x1,x2,y1,y2,op);
	else if(x1>mid)
		return query_x(rr,x1,x2,y1,y2,op);
	else
	{
		if(op==0)
			return max(query_x(ll,x1,mid,y1,y2,op),query_x(rr,mid+1,x2,y1,y2,op));
		if(op==1)
			return min(query_x(ll,x1,mid,y1,y2,op),query_x(rr,mid+1,x2,y1,y2,op));
		if(op==2)
			return query_x(ll,x1,mid,y1,y2,op)+query_x(rr,mid+1,x2,y1,y2,op);
	}
}
void pushupy(int x,int y) 
{
    treex[x].treey[y].maxx=max(treex[x].treey[y<<1].maxx,treex[x].treey[y<<1|1].maxx);
    treex[x].treey[y].minn=min(treex[x].treey[y<<1].minn,treex[x].treey[y<<1|1].minn);
    treex[x].treey[y].sum=treex[x].treey[y<<1].sum+treex[x].treey[y<<1|1].sum;
}
void pushupx(int x,int y) 
{
    treex[x].treey[y].maxx=max(treex[x<<1].treey[y].maxx,treex[x<<1|1].treey[y].maxx);
    treex[x].treey[y].minn=min(treex[x<<1].treey[y].minn,treex[x<<1|1].treey[y].minn);
    treex[x].treey[y].sum=treex[x<<1].treey[y].sum+treex[x<<1|1].treey[y].sum;
}
void change(int x,int y,int v) 
{
    treex[x].treey[y].maxx=v;
    treex[x].treey[y].minn=v;
    treex[x].treey[y].sum=v;
    treex[x].treey[y].val=v;
}
void update(int x,int y,int v)//单点更新 
{
	for(int i=posx[x];i;i>>=1)//向上更新 
	{
		for(int j=posy[y];j;j>>=1)
		{
			if(i==posx[x]&&j==posy[y])
			{
				change(posx[x],posy[y],v);
                continue;
			}
			pushupy(i,j);
		}
		if(i==posx[x]) 
			continue;
        for(int j=posy[y];j;j>>=1) //内层线段树的更新 
		{
            pushupx(i,j);
        }
	} 
}
int Sum(int x,int y) //求 (x,y)对应节点到根路径的元素之和
{
    int sum=0;
    for(int i=posx[x];i;i>>=1) 
	{
        for(int j=posy[y];j;j>>=1) 
		{
            sum+=treex[i].treey[j].val;
        }
    }
    return sum;
}
int main ()
{
	int b,m;
    scanf("%d%d%d",&nx,&b,&m); 
	ny=nx;
    build_x(1,1,nx);
    for(int i=1;i<=nx;i++) 
	{
        for(int j=1;j<=ny;j++) 
		{
            int v; 
			scanf("%d", &v);
            update(i,j,v);
        }
    }
    while(m--) 
	{
        int x,y; 
		scanf("%d%d",&x,&y);
        printf("%d\n",query_x(1,x,x+b-1,y,y+b-1,0)-query_x(1,x,x+b-1,y,y+b-1,1));
    }
    return 0;
}