如何在java中将数组拆分为一半

时间:2015-03-05 21:21:43

标签: java arrays sorting

我需要在对数组进行排序后将其拆分,以便打印类似

的数组

A:[8,7,6,5]

B:[4,3,2,1]

我知道这可能很简单,但我无法弄明白。我需要做x.length / 2这样的事情吗?

 import java.util.Arrays;


public class RecursiveMerge
{

public static void main(String[] args) {
    // TODO Auto-generated method stub
    int [] x= {8,7,5,6,2,4,3,1};
    System.out.println(Arrays.toString(x));
    System.out.println(Arrays.toString(mergeSort(x)));



}

public static int [] mergeSort (int []a)
{
    if(a.length ==1)
        return a;
    else
    {
    int mid =  a.length/2;
    int [] left =mergeSort(Arrays.copyOfRange(a, 0 , mid ));
    int [] right =mergeSort(Arrays.copyOfRange(a, mid, a.length ));

    mergeSort(left);
    mergeSort(right);

    return merge (left, right);
    }
}
public static int[] merge (int[] left, int[] right)
{
int [] result = new int [left.length + right.length];

int leftPtr=0, rightPtr=0, resultPtr=0;


while(leftPtr < left.length && rightPtr < right.length)
    if (left[leftPtr] < right [rightPtr])
        result[resultPtr++] = left[leftPtr++];
    else
        result[resultPtr++] = right[rightPtr++];
while (leftPtr < left.length)
    result[resultPtr++] = left[leftPtr++];
while (rightPtr <right.length)
    result[resultPtr++] = right[rightPtr++];
return result;

}
}

1 个答案:

答案 0 :(得分:3)

要动态制作,请根据数组长度进行分割并将其拆分为两个:

int [] x= {8,7,5,6,2,4,3,1};
int len = x.length;

int a[] = Arrays.copyOfRange(mergeSort(x), 0, len/2);
int b[] = Arrays.copyOfRange(mergeSort(x), (len/2), len);

System.out.println("A: " + Arrays.toString(a));
System.out.println("B: " + Arrays.toString(b));

希望它有所帮助。