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树状数组,inc(x,y)表示对[x-n][y-n]的区域执行一次反转操作,这样,getsum(x,y)将总会包含对[x][y]的操作,即为[x][y]的反转总次数,根据奇偶性判断当前状态。
# include <stdio.h>
# include 
<string.h>

# define N 
1005

int n, c[N][N];
void clr(int nn)
{
                
int i;
                
for (i = 1; i <= nn; ++i)
                                memset(c[i]
+10sizeof(c[0][0])*nn);
}
/******************************************************************/
void inc(int x, int y)
{
                
int t;
                
while (x <= n)
                {
                                t 
= y;
                                
while (t <= n) ++ c[x][t], t += t&(-t);// printf("%d\n", t);
                                x += x&(-x);
                }
}
int getsum(int x, int y)
{
                
int t, ret = 0;
                
while (x > 0)
                {
                                t 
= y;
                                
while (t > 0) ret += c[x][t], t -= t&(-t);// printf("%d\n", t);
                                x -= x&(-x);
                }
                
return ret;
}
/******************************************************************/
int main()
{
                
char ins[3];
                
int X, T, x0, y0, x1, y1;
                scanf(
"%d"&X);
                
while (X--)
                {
                                scanf(
"%d%d"&n, &T), clr(n);
                                
while (T--)
                                {
                                                scanf(
"%s%d%d", ins, &x0, &y0);
                                                
switch(ins[0])
                                                {
                                                                
case 'C':
                                                                {
                                                                                scanf(
"%d%d"&x1, &y1);
                                                                                inc(x0, y0);
                                                                                inc(x0, y1
+1);
                                                                                inc(x1
+1, y0);
                                                                                inc(x1
+1, y1+1);
                                                                                
break;
                                                                }
                                                                
case 'Q': puts((getsum(x0, y0)&0x1? "1":"0"); break;
                                                }
                                }
                                
if (X) putchar('\n');
                }

                
return 0;
}

posted on 2012-09-02 17:29 yajunw 阅读(151) 评论(0)  编辑 收藏 引用

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