"HDU 4819" Mosaic Two-dimensional line segment tree template

Two-dimensional line tree template problem, and one-dimensional thinking, update the time to pay attention to the details.

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/* Two-dimensional line tree template finishing */#include <cstdio> #include <algorithm>using namespace std; #define Lson (pos<<1) #define Rson (pos<<1|1) const int MAXN = 805;const int INF = (1 <<); int n;int posx[maxn],posy[maxn];//positioned Array (Quick Find update interval    , upward recursion)//y direction segment tree interval node struct ny{int l,r; int minv,maxv;};/    /x Direction segment tree interval node struct nx{Ny nodey[maxn << 2];    int l,r;        void build (int l,int r,int pos) {nodey[pos].l = l;        NODEY[POS].R = R;        NODEY[POS].MINV = INF;        NODEY[POS].MAXV =-inf;            if (L = = r) {Posy[l] = pos;        Return        } int mid = (L + r) >> 1;        Build (L,mid,lson);    Build (mid + 1,r,rson);            } int Querymax (int l,int r,int POS) {//l R is the interval that needs to be queried if (L <= nodey[pos].l && nodey[pos].r <= R)        return NODEY[POS].MAXV;        int mid = (nodey[pos].l + nodey[pos].r) >> 1;        int ret =-INF;        if (L <= mid) ret = max (Ret,querymax (L,r,lson)); if (R > mid) ret = max (Ret,querymax (L,r,rson));    return ret;            } int querymin (int l,int r,int POS) {//l R is the interval that needs to be queried if (L <= nodey[pos].l && nodey[pos].r <= R)        return NODEY[POS].MINV;        int mid = (nodey[pos].l + nodey[pos].r) >> 1;        int ret = INF;        if (L <= mid) ret = min (ret,querymin (L,r,lson));        if (R > Mid) ret = min (ret,querymin (L,r,rson));    return ret;    }}NODEX[MAXN << 2];void Build (int l,int r,int pos) {nodex[pos].l = l;    NODEX[POS].R = R;    Nodex[pos].build (1,n,1);        if (L = = r) {Posx[l] = pos;    Return    } int mid = (L + r) >> 1;    Build (L,mid,lson); Build (mid + 1,r,rson);} int Querymax (int x1,int x2,int y1,int y2,int pos) {if (x1 <= nodex[pos].l && nodex[pos].r <= x2) {R    Eturn Nodex[pos].querymax (y1,y2,1);    } int mid = (nodex[pos].l + nodex[pos].r) >> 1;    int ret =-inf;    if (X1 <= mid)    ret = max (Ret,querymax (X1,x2,y1,y2,lson));    if (X2 > Mid) ret = max (Ret,querymax (X1,x2,y1,y2,rson)); return ret;} int querymin (int x1,int x2,int y1,int y2,int pos) {if (x1 <= nodex[pos].l && nodex[pos].r <= x2) {R    Eturn nodex[pos].querymin (y1,y2,1);    } int mid = (nodex[pos].l + nodex[pos].r) >> 1;    int ret = INF;    if (X1 <= mid) ret = min (ret,querymin (X1,x2,y1,y2,lson));    if (X2 > Mid) ret = min (ret,querymin (X1,x2,y1,y2,rson)); return ret;} /* About update here is a difficult point, according to the positioning of the array found to update the node when updating the first round of the x-coordinate segment tree, followed by several rounds of update y-coordinate segment Tree */void update (int x,int y,int value) {int _x = PO    sx[x],_y = Posy[y];    First update the horizontal axis NODEX[_X].NODEY[_Y].MINV = NODEX[_X].NODEY[_Y].MAXV = value;  for (int i = _x; I >= 1; I >>= 1) {if (i! = _x) {nodex[i].nodey[_y].minv = min (nodex[i            << 1].nodey[_y].minv,nodex[i << 1|1].NODEY[_Y].MINV); NODEX[I].NODEY[_Y].MAXV = max (Nodex[i <<        1].nodey[_y].maxv,nodex[i << 1|1].NODEY[_Y].MAXV);            }}//update ordinate segment tree for (int i = _x, I >= 1; I >>= 1) {for (int j = _y; J >= 1; J >>= 1) {            if (j = = _y) continue;            NODEX[I].NODEY[J].MINV = min (nodex[i].nodey[j << 1].minv,nodex[i].nodey[j << 1|1].MINV);        NODEX[I].NODEY[J].MAXV = max (nodex[i].nodey[j << 1].maxv,nodex[i].nodey[j << 1|1].maxv);    }}}int Main () {int t,case = 1;    scanf ("%d", &t);        while (t--) {scanf ("%d", &n);        Build (1,n,1);        int value;                for (int i = 1; I <= n; i++) for (int j = 1; J <= N; j + +) {scanf ("%d", &value);            Update (I,j,value);        } int m,x,y,l;        scanf ("%d", &m);        printf ("Case #%d:\n", case++);            while (m--) {scanf ("%d%d%d", &x,&y,&l); int x1 = x-l/2;            if (X1 < 1) x1 = 1; int x2 = x + l/2;            if (x2 > N) x2 = n; int y1 = y-l/2;            if (Y1 < 1) y1 = 1; int y2 = y + l/2;            if (y2 > N) y2 = n;            int MAXV = Querymax (x1,x2,y1,y2,1);            int MINV = Querymin (x1,x2,y1,y2,1);            int aver = (MAXV + MINV)/2;            printf ("%d\n", aver);        Update (X,y,aver); }} return 0;}

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"HDU 4819" Mosaic Two-dimensional line segment tree template