public static void main(String[] args) {
    int[] a = new int[5];
    for (int i = 0; i < 5; i++) {
        a[i] = (int) (Math.random()*100);
        System.out.print(a[i]+" ");
    }
    /* 反转数组，再输出，只借助一个临时变量*/
    int temp;
    // 以中间数为对称轴，下标加起来和为a.length-1的两个数互换位置
    for(int j=0; j<a.length/2; j++){
        temp = a[j];
        a[j] = a[a.length-1-j];
        a[a.length-1-j] = temp;
    }
    System.out.println("");
    for(int g=0; g<a.length; g++){
        System.out.print(a[g] + " ");
    }
}