HDU 1892 See you~

二维树状数组

#include <cstdio>
#include <algorithm>
using namespace std;
#define N 1005
int c[N][N];
int i,j,n,num,p,T,cnt=1;
int sum(int x,int y){
    int i,j,tmp=0;
    for(i=x;i>0;i-=(i&-i))
      for(j=y;j>0;j-=(j&-j))
        tmp+=c[i][j];
    return tmp;
}
void add(int x,int y,int num){
    for(int i=x;i<N;i+=(i&-i))
      for(int j=y;j<N;j+=(j&-j))
        c[i][j]+=num;
}
void init(){
    for(int i=1;i<N;i++)for(int j=1;j<N;j++)c[i][j]=0;
    for(int i=1;i<N;i++)for(int j=1;j<N;j++)add(i,j,1);
}
void scan(int &x){
    char c;
    while(c=getchar(),c>'9'||c<'0');x=c-'0';
    while(c=getchar(),c<='9'&&c>='0')x=x*10+c-'0';
} 
int main(){
    char s[10];
    char c1,c2;
    int y1,y2,x1,x2;
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        init();
        printf("Case %d:\n",cnt++);
        while(n--){
            c1=getchar();
            if(c1=='A'){
                scan(x1),scan(y1),scan(num);
                add(x1+1,y1+1,num);
            }else if(c1=='S'){
                scan(x1),scan(y1),scan(x2),scan(y2); 
                if(x1<x2) swap(x1,x2); 
                if(y1<y2) swap(y1,y2);
                printf("%d\n",sum(x1+1,y1+1)-sum(x1+1,y2)-sum(x2,y1+1)+sum(x2,y2));
            }else if(c1=='D'){
                scan(x1),scan(y1),scan(num);
                p=sum(x1+1,y1+1)-sum(x1,y1+1)-sum(x1+1,y1)+sum(x1,y1);
                num=p<num?p:num;
                add(x1+1,y1+1,-num);
            }else if(c1=='M'){
                scan(x1),scan(y1),scan(x2),scan(y2),scan(num);
                p=sum(x1+1,y1+1)-sum(x1,y1+1)-sum(x1+1,y1)+sum(x1,y1);
                num=num<p?num:p;
                add(x1+1,y1+1,-num);
                add(x2+1,y2+1,num);
            }else n++;
        }
    }
    return 0;
}