hdu 3929

http://acm.hdu.edu.cn/showproblem.php?pid=3929

Lucas定理

代码

import java.util.*;

public class Main {
    static Scanner in = new Scanner(System.in);
    static long find(long[] a) {
        if(a.length==1)
            return 1l<<Long.bitCount(a[0]);
        long[] b = new long[a.length-1];
        for(int i=0; i<b.length; ++i)
            b[i] = a[i+1];
        long ans = find(b);
        for(int i=0; i<b.length; ++i)
            b[i] &= a[0];
        ans += (1l<<Long.bitCount(a[0]))-2*find(b);
        return ans;
    }
    public static void main(String[] args) {
        final int T=in.nextInt();
        for(int cas=1; cas<=T; ++cas) {
            int N=in.nextInt();
            long[] arr = new long[N];
            for(int i=0; i<N; ++i)
                arr[i] = in.nextLong();
            System.out.println("Case #"+cas+": "+find(arr));
        }
    }
}