SWEA 3750 Digit sum

1 개요

SWEA 3750 Digit sum

SW Expert 아카데미

#	문제	풀이

3 Java

import java.io.*;
import java.util.*;
public class Solution {
	static long f(long n) {
		long sum;
		for(sum=0; n>0; n/=10 ) sum += n%10;
		return sum;
	}
	static long F(long n) {
		for(; n>=10; ) n = f(n);
		return n;
	}
	public static void main(String[] args) throws IOException {
    	Scanner sc = new Scanner(System.in);
    	BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
    	int T = sc.nextInt();
    	for(int tc=1; tc<=T; tc++) {
    		long N = sc.nextLong();
    		bw.append(String.format("#%d %d\n", tc, F(N)));
        }
    	bw.flush();
        sc.close();
    }
}