UVALive - 6709树套树

题意：给你一个矩阵，q次操作，每次查询长宽l的矩阵最大值a和最小值b，然后把中间点换成floor((a+b)/2)，

解法：暴力可过，建n颗线段树暴力更新，但是正解应该是树套树，树套树需要注意的是当建树或修改时pushup操作不能直接搞，要先判断是不是外面层的叶子节点，如果是直接修改，如果不是，应该是从外面层的对应子节点更新过来，因为此时的外层树维护的是x轴区间最大和区间最小，需要从x轴两个更小的区间树合并起来更新

//#pragma comment(linker, "/stack:200000000")

//#pragma GCC optimize("Ofast,no-stack-protector")

//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

//#pragma GCC optimize("unroll-loops")

#include<bits/stdc++.h>

#define fi first

#define se second

#define mp make_pair

#define pb push_back

#define pi acos(-1.0)

#define ll long long

#define vi vector<int>

#define mod 1000000007

#define C 0.5772156649

#define ls l,m,rt<<1

#define rs m+1,r,rt<<1|1

#define pil pair<int,ll>

#define pli pair<ll,int>

#define pii pair<int,int>

#define cd complex<double>

#define ull unsigned long long

#define base 1000000000000000000

#define fio ios::sync_with_stdio(false);cin.tie(0)

using namespace std;

const double g=10.0,eps=1e-;

const int N=+,maxn=+,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f;

int c[N][N],n;

struct segtreeinsegtree{

    int ma[N<<][N<<],mi[N<<][N<<];

    bool leaf;

    void pushupx(int id,int rt)

    {

        ma[id][rt]=max(ma[id<<][rt],ma[id<<|][rt]);

        mi[id][rt]=min(mi[id<<][rt],mi[id<<|][rt]);

    }

    void pushupy(int id,int rt)

    {

        ma[id][rt]=max(ma[id][rt<<],ma[id][rt<<|]);

        mi[id][rt]=min(mi[id][rt<<],mi[id][rt<<|]);

    }

    void buildy(int id,int x,int l,int r,int rt)

    {

        if(l==r)

        {

            if(leaf)ma[id][rt]=mi[id][rt]=c[x][l];

            else pushupx(id,rt);//,printf("%d %d %d %d\n",id,x,ma[id][rt]);

            return ;

        }

        int m=(l+r)>>;

        buildy(id,x,ls);buildy(id,x,rs);

        pushupy(id,rt);

    }

    void buildx(int xl,int xr,int rt,int yl,int yr)

    {

        if(xl==xr){leaf=;buildy(rt,xl,yl,yr,);return ;}

        int m=(xl+xr)>>;

        buildx(xl,m,rt<<,yl,yr);

        buildx(m+,xr,rt<<|,yl,yr);

        leaf=,buildy(rt,xl,yl,yr,);

    }

    void updatey(int id,int posx,int posy,int c,int l,int r,int rt)

    {

        if(l==r)

        {

            if(leaf)ma[id][rt]=mi[id][rt]=c;

            else pushupx(id,rt);

            return ;

        }

        int m=(l+r)>>;

        if(posy<=m)updatey(id,posx,posy,c,ls);

        else updatey(id,posx,posy,c,rs);

        pushupy(id,rt);

    }

    void updatex(int posx,int posy,int c,int l,int r,int rt)

    {

        if(l==r){leaf=;updatey(rt,posx,posy,c,,n,);return ;}

        int m=(l+r)>>;

        if(posx<=m)updatex(posx,posy,c,ls);

        else updatex(posx,posy,c,rs);

        leaf=,updatey(rt,posx,posy,c,,n,);

    }

    int querymay(int id,int L,int R,int l,int r,int rt)

    {

        if(L<=l&&r<=R)return ma[id][rt];

        int m=(l+r)>>,ans=;

        if(L<=m)ans=max(ans,querymay(id,L,R,ls));

        if(m<R)ans=max(ans,querymay(id,L,R,rs));

        return ans;

    }

    int querymax(int xl,int xr,int yl,int yr,int l,int r,int rt)

    {

        if(xl<=l&&r<=xr){return querymay(rt,yl,yr,,n,);}

        int m=(l+r)>>,ans=;

        if(xl<=m)ans=max(ans,querymax(xl,xr,yl,yr,ls));

        if(m<xr)ans=max(ans,querymax(xl,xr,yl,yr,rs));

        return ans;

    }

    int querymiy(int id,int L,int R,int l,int r,int rt)

    {

        if(L<=l&&r<=R)return mi[id][rt];

        int m=(l+r)>>,ans=1e9+;

        if(L<=m)ans=min(ans,querymiy(id,L,R,ls));

        if(m<R)ans=min(ans,querymiy(id,L,R,rs));

        return ans;

    }

    int querymix(int xl,int xr,int yl,int yr,int l,int r,int rt)

    {

        if(xl<=l&&r<=xr)return querymiy(rt,yl,yr,,n,);

        int m=(l+r)>>,ans=1e9+;

        if(xl<=m)ans=min(ans,querymix(xl,xr,yl,yr,ls));

        if(m<xr)ans=min(ans,querymix(xl,xr,yl,yr,rs));

        return ans;

    }

    int query(int x,int y,int l)

    {

        int xl=max(,x-l/),xr=min(n,x+l/);

        int yl=max(,y-l/),yr=min(n,y+l/);

        int ma=querymax(xl,xr,yl,yr,,n,);

        int mi=querymix(xl,xr,yl,yr,,n,);

//        printf("%d %d\n",ma,mi);

        int ans=floor(1.0*(ma+mi)/);

        updatex(x,y,ans,,n,);

        return ans;

    }

    void debug(int id,int l,int r,int rt)

    {

        printf("%d %d %d %d\n",l,r,ma[id][rt],mi[id][rt]);

        if(l==r)return ;

        int m=(l+r)>>;

        debug(id,ls);debug(id,rs);

    }

}s;

int main()

{

    int T,cnt=;scanf("%d",&T);

    while(T--)

    {

        scanf("%d",&n);

        for(int i=;i<=n;i++)

            for(int j=;j<=n;j++)

                scanf("%d",&c[i][j]);

        s.buildx(,n,,,n);

//        s.debug(5,1,n,1);

        int q;scanf("%d",&q);

        printf("Case #%d:\n",++cnt);

        while(q--)

        {

            int x,y,l;

            scanf("%d%d%d",&x,&y,&l);

            printf("%d\n",s.query(x,y,l));

        }

    }

    return ;

}

/***********************

1

3

1 2 3

4 5 6

7 8 9

5

2 2 1

***********************/

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UVALive - 6709树套树

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