POJ1195Mobile phones

二维树状数组板子题。

#include<cstdio>
#include<cstring>
#include<iostream>
#include<cstdlib>
#include<algorithm>
#include<cmath>
#include<vector>
using namespace std;
#define mem(a,b) memset(a,b,sizeof(a))
#define ll long long
#define inf 1000000000
#define maxn 40000
#define eps 1e-12
#define mod 1000000007
#define N 3005
inline int read()
{
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9') {if(ch=='-') f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9') {x=10*x+ch-'0';ch=getchar();}
    return x*f;
}
int c[N][N],n;
int lowbit(int i)
{
    return i&(-i);
}
int sum(int x,int y)
{
    int ret=0;
    for(int i=x;i>0;i-=lowbit(i))
    {
        for(int j=y;j>0;j-=lowbit(j))
          ret+=c[i][j];
    }
    return ret;
}
void add(int x,int y,int d)
{
     for(int i=x;i<=n;i+=lowbit(i))
      for(int j=y;j<=n;j+=lowbit(j))
      {
          c[i][j]+=d;
      }
}
int main()
{
    int k,op,x,y,i,j;
    while(~scanf("%d%d",&i,&n))
    {
        mem(c,0);
        while(1)
        {
            op=read();
            if(op==3) break;
            if(op==1) {
                x=read();y=read();k=read();
                add(x+1,y+1,k);
            }
            else{
                int l,b,r,t;
                l=read();b=read();r=read();t=read();
                l++;b++;r++;t++;
                printf("%d
",sum(r,t)-sum(r,b-1)-sum(l-1,t)+sum(l-1,b-1));
            }
        }
    }
    return 0;
}