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poj2319

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package easy;


import java.io.BufferedInputStream;
import java.util.Scanner;

/**
 *poj2319
 *没用位运算时,513ms 用了位运算后407ms
 *二项式系数C(n,k)=n!/k!/(n-k)!
 * C(1, 0) = C(1, 1) = 1;
 * C(n, 0) = 1对于所有n > 0;
 * C(n, k) = C(n − 1, k − 1) + C(n − 1, k)对于所有0 < k ≤ n.
 * @author NC
 */
public class Poj3219 {

    public static void main(String[] args) {
        Scanner scan = new Scanner(new BufferedInputStream(System.in));
        while (scan.hasNext()) {
            int n = scan.nextInt();
            int k = scan.nextInt();
            if (count2(n) > count2(k) + count2(n - k)) {
                System.out.println(0);
            } else {
                System.out.println(1);
            }
        }
    }

    public static int count2(int n) {
        int count = 0;
         n = n / 2;//用位运算也行n>>1;
        while (n > 0) {
            count = count + n;
            n = n /2 ;
        }
        return count;
    }
}
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