关于#java#的问题，请各位专家解答 hdoj acm问题

Question

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        int t = s.nextInt();
        while (t > 0) {
            int n = s.nextInt();
            int[] arr = new int[n];
            for (int i = 0; i <= n - 1; i++) {
                arr[i] = s.nextInt();
            }
            if(t!=1) {
                if (selectionSort(arr)) {
                    System.out.println("YES");
                } else {
                    System.out.println("NO");
                }
            }else{
                if(selectionSort(arr)){
                    System.out.print("YES");
                }else {
                    System.out.print("NO");
                }
            }
            t--;
        }
    }
    public static int gcd(int m, int n) {
        int i = 0, t, x;
        while (m % 2 == 0 & n % 2 == 0) {
            m /= 2;
            n /= 2;
            i++;
        }
        if (m < n) {
            t = m;
            m = n;
            n = t;
        }
        while (n != (m - n)) {
            x = m - n;
            m = (n > x) ? n : x;
            n = (n < x) ? n : x;
        }
        if (i == 0)
            return n;
        else
            return (int) Math.pow(2, i) * n;
    }

    public static boolean selectionSort(int[] a) {
        int N = a.length;
        if (N==0){
            return true;
        }
        int minNum = getMin(a);
        for (int i = 0; i < N - 1; i++) {
            //length = 5   i = 0 1 2 3 4   i= 0 j =1234
            int min = i;
            for (int j = i + 1; j < N; j++) {
                //将a[i]和a[i+1...N-1]中的最小元素交换
                if (a[j] < a[min]) {//升序排列
                    min = j;
                }
            }
            if (min != i) {//一下是排序过程 a[min]跟a[i]进行交换
                if (gcd(a[min], a[i]) != minNum) {
                    return false;
                } else {//要不然就一直排序下去
                    int temp = a[i];
                    a[i] = a[min];
                    a[min] = temp;
                }
            }

        }
        return true;
    }
        public static int getMin (int[] arr){
            int minNum = arr[0];
            for (int i = 1; i < arr.length; i++) {
                if (minNum > arr[i]) {
                    minNum = arr[i];
                }
            }
            return minNum;
        }
    }

自测的时候都没什么问题 但是 已提交就是wrong answer 这是为什么呢？

Answer 1

说明只有测试样例对了，真正测评的时候他的数据可能是边界的测试