Java程序以给定大小的组反转数组
通过反转所需大小的子数组，可以按给定大小的组反转数组。一个例子如下。
Array = 1 2 3 4 5 6 7 8 9 10 Group size = 3 Modified array = 3 2 1 6 5 4 9 8 7 10
演示此过程的程序如下。
示例
public class Example {
public static void main(String[] args) {
int arr[] = {1, 2, 3, 4, 5, 6, 7, 8, 9 ,10};
int size = 4;
int n = arr.length;
System.out.print("Original array is: ");
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
for (int i = 0; i < n; i += size) {
int left = i;
int right = Math.min(i + size - 1, n - 1);
int temp;
while (left < right) {
temp = arr[left];
arr[left] = arr[right];
arr[right] = temp;
left += 1;
right -= 1;
}
}
System.out.print("\nModified array is: ");
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
}
}输出结果
Original array is: 1 2 3 4 5 6 7 8 9 10 Modified array is: 4 3 2 1 8 7 6 5 10 9
现在让我们了解上面的程序。
首先打印原始数组。然后，使用for循环将给定大小（即4）的组反转为数组。演示此操作的代码段如下所示。
System.out.print("Original array is: ");
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
for (int i = 0; i < n; i += size) {
int left = i;
int right = Math.min(i + size - 1, n - 1);
int temp;
while (left < right) {
temp = arr[left];
arr[left] = arr[right];
arr[right] = temp;
left += 1;
right -= 1;
}
}然后显示修改后的数组。演示此过程的代码段如下所示。
System.out.print("\nModified array is: ");
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");