牛牛的身高错在哪里了？

import java.util.Scanner;
public class Main {

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int t = sc.nextInt();
    for (int i = 0; i < t; i++) {
        int a = Integer.parseInt(sc.next());
        int ch = 10;
        while (a / ch > 0) {
            int y = a % ch;
            if (y >= ch /2) {
                a = a + (ch - y);
            }
            ch *= 10;
        }
        System.out.println(a);
    }
}
}