HDU1892 二维树状数组 区间求和,单点修改

传送门：二维树状数组模板题

分析：二维树状数组模板题，求区间和 跟 单点修改

代码如下：

#include 
#include 
#include 
using namespace std;

const int maxn = 1000+10;
const int N = 1005;
int a[maxn][maxn];
int c[maxn][maxn];

inline int lowbit(int x) {return x&(-x); }
inline void update(int x, int y, int val) {
    for (int i=x; i<=N; i += lowbit(i))
        for (int j=y; j<=N; j += lowbit(j)) c[i][j] += val;
}

inline int query(int x, int y) {
    int sum = 0;
    for (int i=x; i>0; i -= lowbit(i))
        for (int j=y; j>0; j -= lowbit(j) ) sum += c[i][j];
    return sum;
}

inline int Min(int x, int y) {return xX2) swap(X1,X2);
               if (Y1>Y2) swap(Y1,Y2);
               X1++; Y1++; X2++; Y2++;
               printf("%d\n",query(X2,Y2)-query(X2,Y1-1)-query(X1-1,Y2)+query(X1-1,Y1-1));
          }
          else if (s[0] == 'A') {
               scanf("%d%d%d",&x,&y,&val);
               x++; y++;
               update(x,y,val);
               a[x][y] += val;
          }
          else if (s[0] == 'D' ){
              scanf("%d%d%d",&x,&y,&val);
              x++; y++;
              val = Min(a[x][y],val);
              update(x,y,-val);
              a[x][y] -= val;
          }
          else {
              scanf("%d%d%d%d%d",&X1,&Y1,&X2,&Y2,&val);
              X1++; Y1++; X2++; Y2++;
              val = Min(a[X1][Y1],val);
              update(X1,Y1,-val);
              update(X2,Y2,val);
              a[X1][Y1] -= val;
              a[X2][Y2] += val;
          }

       }
    }
    return 0;
}