Uva 11297 Census，二维线段树，板子

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维护二维矩阵。
q x1, y1, x2, y2 : 查询x1<=x<=x2, y1<=y<=y2的格子(x,y)的最大值和最小值。
c x, y, v: 修改(x,y) = v。
矩阵大小(n,m<=500)。
查询次数q<=40000。
#include<algorithm>using namespace std;const int INF = 1<<30;const int maxn = 2000 + 10;int A[maxn][maxn];struct IntervalTree2D {    int Max[maxn][maxn], Min[maxn][maxn], n, m;    int xo, xleaf, row, x1, y1, x2, y2, x, y, v, vmax, vmin; // 参数、查询结果和中间变量    void query1D(int o, int L, int R) {        if(y1 <= L && R <= y2) {            vmax = max(Max[xo][o], vmax);            vmin = min(Min[xo][o], vmin);        } else {            int M = L + (R-L)/2;            if(y1 <= M) query1D(o*2, L, M);            if(M < y2) query1D(o*2+1, M+1, R);        }    }    void query2D(int o, int L, int R) {        if(x1 <= L && R <= x2) {            xo = o;            query1D(1, 1, m);        } else {            int M = L + (R-L)/2;            if(x1 <= M) query2D(o*2, L, M);            if(M < x2) query2D(o*2+1, M+1, R);        }    }    void modify1D(int o, int L, int R) {        if(L == R) {            if(xleaf) {                Max[xo][o] = Min[xo][o] = v;                return;            }            Max[xo][o] = max(Max[xo*2][o], Max[xo*2+1][o]);            Min[xo][o] = min(Min[xo*2][o], Min[xo*2+1][o]);        } else {            int M = L + (R-L)/2;            if(y <= M) modify1D(o*2, L, M);            else modify1D(o*2+1, M+1, R);            Max[xo][o] = max(Max[xo][o*2], Max[xo][o*2+1]);            Min[xo][o] = min(Min[xo][o*2], Min[xo][o*2+1]);        }    }    void modify2D(int o, int L, int R) {        if(L == R) {            xo = o;            xleaf = 1;            modify1D(1, 1, m);        } else {            int M = L + (R-L)/2;            if(x <= M) modify2D(o*2, L, M);            else modify2D(o*2+1, M+1, R);            xo = o;            xleaf = 0;            modify1D(1, 1, m);        }    }    // 只构建xo为叶子（即x1=x2）的y树    void build1D(int o, int L, int R) {        if(L == R) Max[xo][o] = Min[xo][o] = A[row][L];        else {            int M = L + (R-L)/2;            build1D(o*2, L, M);            build1D(o*2+1, M+1, R);            Max[xo][o] = max(Max[xo][o*2], Max[xo][o*2+1]);            Min[xo][o] = min(Min[xo][o*2], Min[xo][o*2+1]);        }    }    void build2D(int o, int L, int R) {        if(L == R) {            xo = o;            row = L;            build1D(1, 1, m);        } else {            int M = L + (R-L)/2;            build2D(o*2, L, M);            build2D(o*2+1, M+1, R);            for(int i = 1; i <= m*4; i++) {                Max[o][i] = max(Max[o*2][i], Max[o*2+1][i]);                Min[o][i] = min(Min[o*2][i], Min[o*2+1][i]);            }        }    }    void query() {        vmax = -INF;        vmin = INF;        query2D(1, 1, n);    }    void modify() {        modify2D(1, 1, n);    }    void build() {        build2D(1, 1, n);    }};IntervalTree2D t;#include<cstdio>int main() {    int n, m, Q, x1, y1, x2, y2, x, y, v;    char op[10];    scanf("%d%d", &n, &m);    t.n = n;    t.m = m;    for(int i=1; i<=n; ++i)        for(int j=1; j<=m; ++j)            scanf("%d", &A[i][j]);    t.build();    scanf("%d", &Q);    while(Q--) {        scanf("%s", op);        if(op[0]=='q') {            scanf("%d%d%d%d", &t.x1, &t.y1, &t.x2, &t.y2);            t.query();            printf("%d %d\n", t.vmax, t.vmin);        } else {            scanf("%d%d%d", &t.x, &t.y, &t.v);            t.modify();        }    }    return 0;}
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