Array usage

Time:2022-5-21

Array usage

For loop

package com.HuoLong.array;

public class ArrayDemo03 {
   public static void main(String[] args) {
       int[] array={1,2,3,4,5};//Write dead

       //Print all array elements
       for (int i = 0; i <array.length ; i++) {
           System.out.println(array[i]);
      }
       System.out.println("============");
       //Calculate the sum of all elements
       int sum=0;
       for (int i = 0; i < array.length ; i++) {
           sum=sum+array[i];
      }
       System.out.println("sum="+sum);
       System.out.println("============");
       //Find maximum element
       int max=array[0];

       for (int i = 1; i <array.length ; i++) {
           if (array[i]>max){
               max=array[i];
      }

  }System.out.println("max="+max);


}}

For each loop

First, define an array int [] arrays = {1,2,3,4,5}; Then arrays For + space, and then the output is array, as follows:

public class ArrayDemo04 {
   public static void main(String[] args) {
       int[] arrays={1,2,3,4,5};
       //Enhanced for loop # for printout
       for (int array : arrays) {
           System.out.println(array);
      }//For each loop

Array as method input parameter

Define a printarray method below. Write int [] arrays (arguments) for the parameters of the method (int [] arrays = {1, 2, 3, 4, 5} has been established in the main method), then write the method body in the method, call it in the main method and output.

package com.HuoLong.array;

public class ArrayDemo04 {
   public static void main(String[] args) {
       int[] arrays={1,2,3,4,5};
          printArray(arrays);
  }
   /// / print array elements
   public static void printArray(int[] arrays){
       for (int i = 0; i < arrays.length; i++) {
           System.out.print(arrays[i]+" ");

      }

  }
}

Return value as array

Generally, this kind of inversion array is used. Modify the contents of the array, and then return a new array, as follows:

package com.HuoLong.array;
//Reverse return value name
//Printarrays array can be called as an input parameter
public class ArrayDemo04 {
   public static void main(String[] args) {
       int[] arrays={1,2,3,4,5};
       //Enhanced for loop # for printout
//       for (int array : arrays) {
////           System.out.println(array);
//} / / for each loop
//       printArray(arrays);
       int[] reverses = reverse(arrays);
       printArray(reverses);
  }
   public static int[] reverse(int[] arrays){
       int[] result=new int[arrays.length];
       for (int i = 0,j= arrays.length-1; i < arrays.length; i++,j--) {
           result[j]=arrays[i];

      }
       return result;
  }




/// / print array elements
   public static void printArray(int[] arrays){
       for (int array : arrays) {
           System.out.print(array + " ");

      }

  }

  }