算法——线性结构的简单应用

package com.demo.calculate;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;

import java.util.Arrays;

public class MainActivity extends AppCompatActivity {
    private int[] arr;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        arr = new int[]{2,3,4,5,6,7,8,9};
        findViewById(R.id.btn_add).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                addElementToLast(11);
            }
        });
        findViewById(R.id.btn_insert).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                insertElement(2,5);
            }
        });
        findViewById(R.id.btn_delete).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                deleteElement(2);
            }
        });
        findViewById(R.id.btn_lineSearch).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.i("tag",lineSearch(2)+"");
            }
        });
        findViewById(R.id.btn_addQueue).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               addQueue(10);
            }
        });
        findViewById(R.id.btn_popQueue).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                popQueue();
            }
        });
        findViewById(R.id.btn_bubbleSort).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                bubbleSort();
            }
        });
    }

    /**
     * 冒泡排序
     */
    private void bubbleSort() {
        int[] arr = new int[]{3,2,5,7,4,1,0,8};
        for (int i = 0; i <arr.length-1 ; i++) {
            for (int j = 0; j <arr.length-1-i ; j++) {
                //交换位置
                if (arr[j]>arr[j+1]){
                    int temp = arr[j];
                    arr[j] = arr[j+1];
                    arr[j+1] = temp;
                }
            }
        }
        Log.i("tag",Arrays.toString(arr));
    }

    /**
     * 出队
     */
    private void popQueue() {
        if (arr.length==0){
            return;
        }
        int[] newArr = new int[arr.length-1];
        for (int i = 0; i <newArr.length ; i++) {
            newArr[i] = arr[i+1];
        }
        arr = newArr;
        Log.i("tag",Arrays.toString(arr));
    }

    /**
     *入队
     */
    private void addQueue(int element) {
        int[] newArr = new int[arr.length+1];
        for (int i = 0; i <arr.length ; i++) {
            newArr[i] = arr[i];
        }
        newArr[arr.length] = element;
        arr = newArr;
        Log.i("tag",Arrays.toString(arr));
    }
    /**
     *线性查找
     */
    private int lineSearch(int index) {
        for (int i = 0; i <arr.length ; i++) {
            if (arr[i] == index){
               return i;
            }
        }
        return -1;
    }

    /**
     *删除元素
     */
    private void deleteElement(int index) {
        if (index<0 || index>arr.length-1){
            return;
        }
        int[] newArr = new int[arr.length-1];
        for (int i = 0; i <newArr.length ; i++) {
            if (i<index){
                newArr[i] = arr[i];
            }else{
                newArr[i] = arr[i+1];
            }
        }
        arr = newArr;
        Log.i("tag",Arrays.toString(arr));
    }

    /**
     * 往数组的末尾添加元素
     */
    private void addElementToLast(int element) {
        int[] newArr = new int[arr.length+1];
        for (int i = 0; i <arr.length ; i++) {
            newArr[i] = arr[i];
        }
        newArr[arr.length] = element;
        arr = newArr;
        Log.i("tag", Arrays.toString(arr));
    }
    /**
     * 往数组的中间插入元素
     * @param index
     * @param element
     */
    private void insertElement(int index, int element) {
        int[] newArr = new int[arr.length+1];
        if (index<0 || index>arr.length-1){
            return;
        }
        for (int i = 0; i <arr.length; i++) {
            if (i<index){
                newArr[i] = arr[i];
            }else{
                newArr[i+1] = arr[i];
            }
        }
        newArr[index] = element;
        arr = newArr;
        Log.i("tag",Arrays.toString(arr));
    }

}