Array inversion JAVA

ReversalArray——The implementation method of Java language

Method 1:The order of the front and back is reversed

public class Array{
		public static void main(String[] args){
			  int[] arr={1,2,5,7,3};        //Statually initialize a set of arrays
			  for (int k=0;k<arr.length/2;k++){
            int w=arr[k];				 	//Storage array elements with the help of the third variable
            arr[k]=arr[arr.length-1-k];// Switch array elements corresponding to k and -1-k
            arr[arr.length-1-k]=w;
        }
       for (int k = 0; k < 5; k++) {
           System.out.print(arr[k]+"  ");
        }
   }
}

Method 2: Climb the two sides (the name you give me) - approaching

public class Array{
	public static void main(String[] args){
		int[] arr={1,2,3,4,5};// Static initialization
		for(int m=0,n=4;m<n;m++,n--){     //n=-1；
            int t=arr[m];
            arr[m]=arr[n];
            arr[n]=t;
        }

        for (int k = 0; k < 5; k++) {
            System.out.print(arr[k]+" ");
        }
  }
}

Method 3: Create an empty array

public class Array{
	public static void main(String[] args){
			int[] arr={1,2,3,4,5};
			int[] A = new int[arr.length]; //Create an empty array A of large size with arr to be used
        
        for (int i=0;i<arr.length;i++){	//Invert the arr element and assign it to array A as a whole
            A[i] = arr[arr.length-i-1];
        }
        
        for (int i=0;i<A.length;i++){	//The purpose is to invert the original array.  Then assign the inverted array A to the original array arr for output
            arr[i] = A[i];
            System.out.print(arr[i]+" ");
        }
	}
}