zoj 3284 Matrix Processing(二维树状数组)

http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=3623

　　简单二维树状数组题。单点询问，两种更新（按行或者按列）。直接用二维的线段树，最多将更新的区间划分为3个。

代码如下：

#include <cstdio>
#include <cstdlib>
#include <algorithm>

using namespace std;

const int size = 105;

struct BIT2D {
    int key[size][size];
    int row, col; //   x-row   y-col

    void init() {
        for (int i = 0; i <= row; i++) {
            for (int j = 0; j <= col; j++) {
                key[i][j] = 0;
            }
        }
    }

    void addMain(int x, int y, int k) {
        if (!x || !y) return ;
        for (int i = x; i > 0; i -= (-i) & i) {
            for (int j = y; j > 0; j -= (-j) & j) {
                key[i][j] += k;
            }
        }
    }

    void add(int x1, int y1, int x2, int y2, int k) {
        addMain(x1 - 1, y1 - 1, k);
        addMain(x1 - 1, y2, -k);
        addMain(x2, y1 - 1, -k);
        addMain(x2, y2, k);
    }

    int getPoint(int x, int y) {
        int ret = 0;

        for (int i = x; i <= row; i += (-i) & i) {
            for (int j = y; j <= col; j += (-j) & j) {
                ret += key[i][j];
            }
        }

        return ret;
    }
} BIT;

void addCol(int x1, int y1, int x2, int y2, int k) {
    if (x1 == x2) {
        BIT.add(x1, y1, x2, y2, k);
    } else {
        BIT.add(x1, y1, x1, BIT.col, k);
        if (x2 - x1 > 1) {
            BIT.add(x1 + 1, 1, x2 - 1, BIT.col, k);
        }
        BIT.add(x2, 1, x2, y2, k);
    }
}

void addRow(int x1, int y1, int x2, int y2, int k) {
    if (y1 == y2) {
        BIT.add(x1, y1, x2, y2, k);
    } else {
        BIT.add(x1, y1, BIT.row, y1, k);
        if (y2 - y1 > 1) {
            BIT.add(1, y1 + 1, BIT.row, y2 - 1, k);
        }
        BIT.add(1, y2, x2, y2, k);
    }
}

int main() {
    int Case = 1, m;

//    freopen("in", "r", stdin);
    while (~scanf("%d%d", &BIT.row, &BIT.col)) {
        BIT.init();
        printf("Case %d\n", Case);
        Case++;
        for (int i = 1, x; i <= BIT.row; i++) {
            for (int j = 1; j <= BIT.col; j++) {
                scanf("%d", &x);
                addRow(i, j, i, j, x);
            }
        }
        /*
        for (int i = 1; i <= BIT.row; i++) {
            for (int j = 1; j <= BIT.col; j++) {
                printf("%d ", BIT.getPoint(i, j));
            }
            puts("");
        }
        */
        scanf("%d", &m);

        int op, a, b, c, d, e;

        while (m--) {
            scanf("%d", &op);
            if (op == 0) {
                scanf("%d%d%d%d%d", &a, &b, &c, &d, &e);
                if (a > c) {
                    swap(a, c);
                    swap(b, d);
                } else if (a == c && b > d) {
                    swap(b, d);
                }
                addCol(a, b, c, d, e);
            } else if (op == 1) {
                scanf("%d%d%d%d%d", &a, &b, &c, &d, &e);
                if (b > d) {
                    swap(b, d);
                    swap(a, c);
                } if (b == d && a > c) {
                    swap(a, c);
                }
                addRow(a, b, c, d, e);
            } else {
                scanf("%d%d", &a, &b);
                printf("%d\n", BIT.getPoint(a, b));
            }
            /*
            for (int i = 1; i <= BIT.row; i++) {
                for (int j = 1; j <= BIT.col; j++) {
                    printf("%d ", BIT.getPoint(i, j));
                }
                puts("");
            }
            */
        }
    }

    return 0;
}

——written by Lyon