Java面试题：有数组a[n]，用java代码将数组元素顺序颠倒

 

/**
 * 颠倒数组数据的先后顺序
 *
 * @author 老紫竹 java2000.net
 */
public class Test {
  public static void reverse(int[] a, int left, int right) {
    if (left >= right)
      return;
    int temp;
    temp = a[left];
    a[left] = a[right];
    a[right] = temp;
    reverse(a, ++left, --right);
  }

  public static void main(String args[]) {
    int[] a = { 1, 2, 3, 4, 5 };
    reverse(a, 0, a.length - 1);
    for (int i = 0; i < a.length; i++)
      System.out.println(a[i]);
  }
}

/**
 * 颠倒数组数据的先后顺序
 * 
 * @author 老紫竹 java2000.net
 */
public class Test {
  public static void reverse(int[] a, int left, int right) {
    if (left >= right)
      return;
    int temp;
    temp = a[left];
    a[left] = a[right];
    a[right] = temp;
    reverse(a, ++left, --right);
  }

  public static void main(String args[]) {
    int[] a = { 1, 2, 3, 4, 5 };
    reverse(a, 0, a.length - 1);
    for (int i = 0; i < a.length; i++)
      System.out.println(a[i]);
  }
}

从字符串的两端开始交换，然后缩短字符串的长度，从新的两端开始。