Java 删除数组的头部元素，尾部元素，数组中的特定值

小半 • 2023年2月9日下午5:03 • 技术随笔 • 阅读 200

删除数组的头部元素，尾部元素，数组中的特定值

例如，数组{1,2,3,3,6,4,5,6,6,6,6},删除头部元素，结果：{2,3,3,6,4,5,6,6,6,6}
数组{1,2,3,3,6,4,5,6,6,6,6},删除尾部元素，结果：{1,2,3,3,6,4,5,6,6,6}
数组{1,2,3,3,6,4,5,6,6,6,6},删除数组中元素6，结果: {1,2,3,3,4,5}

package com.wysheng.src1;
import java.util.Arrays;
/**
 * @author Wang Yongsheng
 * @version 1.0
 * @date 2021/10/16 13:58
 */
public class TestDemo03 {
    //删除头部
    public static int[] removeHead(int[] arr) {
        if(arr == null) {
            return null;
        }
        for (int i = 0; i < arr.length - 1; i++) {
            arr[i] = arr[i + 1];
        }
        int[] brr = new int[arr.length - 1];

        for (int i = 0; i < arr.length - 1; i++) {
            brr[i] = arr[i];
        }
        return brr;
    }

    //删除尾部
    public static int[] removeTail(int arr[]) {
        if(arr == null) {
            return null;
        }
        int[] brr = new int[arr.length - 1];
        for (int i = 0; i < brr.length; i++) {
            brr[i] = arr[i];
        }
        return brr;
    }

    //删除特定值
    public static int[] removeValue(int[] arr, int value) {
        //安全检测
        if (arr == null) {
            return null;
        }
        int count = 0;
        for (int i = 0; i < arr.length - count; ) {
            if (arr[i] == value) {
                count++;
                for (int j = i + 1; j < arr.length; j++) {
                    arr[j - 1] = arr[j];
                }
            } else {
                i++;
            }
        }
        arr = Arrays.copyOf(arr,arr.length - count);
        return arr;
    }

    public static void main(String[] args) {
        int[] arr1 = {1,2,3,3,6,4,5,6,6,6,6};
        System.out.println("------删除头部元素------");
        int[] brr = removeHead(arr1);
        System.out.println(Arrays.toString(brr));
        System.out.println("------删除尾部元素------");
        int[] arr2 = {1,2,3,3,6,4,5,6,6,6,6};
        int[] crr = removeTail(arr2);
        System.out.println(Arrays.toString(crr));
        System.out.println("------删除特定元素------");
        int[] arr3 = {1,2,3,3,6,4,5,6,6,6,6};
        arr3 = removeValue(arr3, 6);
        System.out.println(Arrays.toString(arr3));
    }
}