【树状数组】[CodeForces - 341D]Iahub and Xors

CodeForces - 341D
分析:异或有一个性质:a^b=c,a^c=b,b^c=a;
然后就可以,直接用二维树状数组,具体还可以参见上帝造题的七分钟

代码:

#include<cstdio>
#define MAXN 1000
int n,m,c[MAXN+10][MAXN+10],ci[MAXN+10][MAXN+10],cj[MAXN+10][MAXN+10],cij[MAXN+10][MAXN+10];
void Read(int &x){
    char c;
    while(c=getchar(),c!=EOF)
        if(c>='0'&&c<='9'){
            x=c-'0';
            while(c=getchar(),c>='0'&&c<='9')
                x=x*10+c-'0';
            ungetc(c,stdin);
            return;
        }
}
inline int lowbit(int x){
    return x&-x;
}
void update(int c[][MAXN+10],int x,int y,int d){
    int j;
    for(;x<=n;x+=lowbit(x))
        for(j=y;j<=n;j+=lowbit(j))
            c[x][j]^=d;
}
int getsum(int c[][MAXN+10],int x,int y){
    int j,ret=0;
    for(;x;x-=lowbit(x))
        for(j=y;j;j-=lowbit(j))
            ret^=c[x][j];
    return ret;
}

int main()
{
    Read(n),Read(m);
    int p,x1,y1,x0,y0,v,a1,a2,a3,a4;
    while(m--){
        Read(p);
        if(p==2){
            Read(x0),Read(y0),Read(x1),Read(y1),Read(v);
            update(c,x0,y0,v);
            update(ci,x0,y0,x0&1?v:0);
            update(cj,x0,y0,y0&1?v:0);
            update(cij,x0,y0,(x0*y0)&1?v:0);
            update(c,x0,y1+1,v);
            update(ci,x0,y1+1,x0&1?v:0);
            update(cj,x0,y1+1,(y1+1)&1?v:0);
            update(cij,x0,y1+1,(x0*(y1+1))&1?v:0);
            update(c,x1+1,y0,v);
            update(ci,x1+1,y0,(x1+1)&1?v:0);
            update(cj,x1+1,y0,y0&1?v:0);
            update(cij,x1+1,y0,((x1+1)*y0)&1?v:0);
            update(c,x1+1,y1+1,v);
            update(ci,x1+1,y1+1,(x1+1)&1?v:0);
            update(cj,x1+1,y1+1,(y1+1)&1?v:0);
            update(cij,x1+1,y1+1,((x1+1)*(y1+1))&1?v:0);
        }
        else{
            Read(x0),Read(y0),Read(x1),Read(y1);
            a1=(((x1+1)*(y1+1))&1?getsum(c,x1,y1):0)^((y1+1)&1?getsum(ci,x1,y1):0)^((x1+1)&1?getsum(cj,x1,y1):0)^getsum(cij,x1,y1);
            a2=((x0*(y1+1))&1?getsum(c,x0-1,y1):0)^((y1+1)&1?getsum(ci,x0-1,y1):0)^(x0&1?getsum(cj,x0-1,y1):0)^getsum(cij,x0-1,y1);
            a3=(((x1+1)*y0)&1?getsum(c,x1,y0-1):0)^(y0&1?getsum(ci,x1,y0-1):0)^((x1+1)&1?getsum(cj,x1,y0-1):0)^getsum(cij,x1,y0-1);
            a4=((x0*y0)&1?getsum(c,x0-1,y0-1):0)^(y0&1?getsum(ci,x0-1,y0-1):0)^(x0&1?getsum(cj,x0-1,y0-1):0)^getsum(cij,x0-1,y0-1);
            printf("%d\n",a1^a2^a3^a4);
        }
    }
}
posted @ 2015-09-26 22:54  outer_form  阅读(157)  评论(0编辑  收藏  举报