2982054_re.java

来自「北大大牛代码 1240道题的原代码 超级权威」· Java 代码 · 共 33 行

import java.util.*;
import java.math.*;

public class Main {

	public static void main(String[] args) {

		Scanner cin = new Scanner (System.in);
		BigInteger ans = BigInteger.ONE;
		BigInteger num;
		BigInteger zero = BigInteger.ZERO;
		BigInteger n[] = new BigInteger [10001];
		int i;
		
		num = cin.nextBigInteger();
		n[0] = BigInteger.ONE;
		for(i = 1; i <= 10000; i++)
		{
			n[i] = n[i-1].add(n[i-1]);
		}
		for(i = 0; n[i].compareTo(num) < 0; i++)
		{
			if(!n[i].and(num).equals(zero))
			{
				ans = ans.add(ans);
			}
		}
		ans = ans.subtract(BigInteger.ONE);
		System.out.println(ans);
	}

}