数组

一:初始化

一维：int a[] = {1,2,3,4,5,6,7,8};

二维：int A[][]={1,3,5,7},{2,4,6,8};

 

二:数组相关方法

搜索

package one;

import java.util.Arrays;

public class Shuz {

    public static void main(String[] args) {
        int A[] = {11,4,5,12,6,24,25}; 
        Arrays.sort(A);//排序
        int location = Arrays.binarySearch(A, 5);
        
        System.out.print("排序后的数组为：");
        for(int i = 0; i < A.length; i++){
            System.out.print(+A[i] + " ");
        }
        System.out.println();
        System.out.println("查找5的位置是 " + location);

    }

}

排序：

package one;

import java.util.Arrays;

public class paixu {
    public static void main(String[] args) {
        String a[] = new String[] {"100","abc","abcd","200"};
        Arrays.sort(a);
        System.out.println(Arrays.asList(a));
    }

}

 

 

动态数组：

package one;

import java.util.ArrayList;

public class JavaArrayList {

    public static void main(String[] args) {
        ArrayList a = new ArrayList();
        a.add("a");
        a.add("b");
        a.add("c");
        for(int i=0; i<a.size(); i++){
            String alEach = (String)a.get(i);
            System.out.println(alEach);
        }
        
        a.remove(1);
        a.add(1,"2");
        for(int i=0; i<a.size(); i++){
            String alEach = (String)a.get(i);
            System.out.println(alEach);
        }
    }
}

 

遍历（foreach循环）：

package one;

public class TestForEach {

    public static void main(String[] args) {
        String books[] = {"java", "C", "C++"};
        for (String book :books){
            System.out.println(book);
        }
    }
}