自测-4 Have Fun with Numbers（20 分）

Notice that the number 123456789 is a 9-digit number consisting exactly the numbers from 1 to 9, with no duplication. Double it we will obtain 246913578, which happens to be another 9-digit number consisting exactly the numbers from 1 to 9, only in a different permutation. Check to see the result if we double it again!

Now you are suppose to check if there are more numbers with this property. That is, double a given number with k digits, you are to tell if the resulting number consists of only a permutation of the digits in the original number.

Input Specification:

Each input contains one test case. Each case contains one positive integer with no more than 20 digits.

Output Specification:

For each test case, first print in a line "Yes" if doubling the input number gives a number that consists of only a permutation of the digits in the original number, or "No" if not. Then in the next line, print the doubled number.

Sample Input:

1234567899
Sample Output:

Yes
2469135798

import java.math.BigInteger;
import java.util.Scanner;


public class Main{
    public static boolean judge(String nums,String doubled){
        char []exaclty = new char[10];
        if (nums.length() != doubled.length()) {
            return false;
        }
        for (int i = 0; i < nums.length(); i++) {
            int num = nums.charAt(i) - '0';
            exaclty[num]++;
        }
        for (int i = 0; i < doubled.length(); i++) {
            int num = doubled.charAt(i)-'0';
            exaclty[num]--;
        }
        for (int i = 0; i < exaclty.length; i++) {
            if (exaclty[i] != 0) {
                return false;
            }
        }
        return true;
    }
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String nums = in.next();
        BigInteger doubling = new BigInteger(nums);
        doubling = doubling.shiftLeft(1);
        String doubled = String.valueOf(doubling);
        if (judge(nums,doubled)) {
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
        System.out.println(doubling);
    }
}