java怎么取数组中间

int[] arr = {1, 2, 3, 4, 5};
int middleElement = arr[arr.length / 2]; // 3

int[] arr = {1, 2, 3, 4};
int middleElement1 = arr[arr.length / 2]; // 3
int middleElement2 = arr[arr.length / 2 - 1]; // 2
double average = (middleElement1 + middleElement2) / 2.0; // 2.5

import java.util.Arrays;

public class MiddleElement {

    public static void main(String[] args) {
        int[] arr1 = {1, 2, 3, 4, 5};
        int[] arr2 = {1, 2, 3, 4};

        System.out.println("奇数长度数组：" + Arrays.toString(arr1));
        System.out.println("中间元素：" + findMiddleElement(arr1)); // 3

        System.out.println("偶数长度数组：" + Arrays.toString(arr2));
        System.out.println("中间元素：" + findMiddleElement(arr2)); // 2.5
    }

    public static int findMiddleElement(int[] arr) {
        if (arr.length % 2 == 1) {
            return arr[arr.length / 2];
        } else {
            return (arr[arr.length / 2] + arr[arr.length / 2 - 1]) / 2;
        }
    }
}