Related knowledge of arrays

array Default value comparison chart

Array type	Default values for array elements
BYTE, short, int, long	0
float, double	0.0
Char	' + '
Boolean	False
Object.type	Null

Related Operations for arrays:

1. Array length

Syntax format: array name. length

2. Array padding

Syntax format: Arrays.fill (array name, value) Arrays.fill (array name, start subscript, end subscript, value)

Note: When assigning to arrays using the Fill method of arrays, you can specify the starting position begin and end position end, which will only assign to the array elements in the following table for the [begin,end] interval.

3. Array replication

Syntax format: Arraycopy (array A, start copying subscript, copy to array B, start copy subscript, copy length)

4. Array comparison

Syntax format: arrays.equals (array 1, array 2) return value to Boolean type

5. Array sorting

Syntax format: Arrays.sort (Array)

6. Finding array elements

Syntax format: arrays.binarysearch (array) binary lookup operation

ImportJava.lang.reflect.Array;Importjava.util.Arrays; Public classJavaTest2ImplementsJavaTest1 { Public Static voidMain (string[] args) {int[][]a={{1,2,3},{4,8},{5,7,6}}; int[][]b={{1,2,3},{1,2,3,4},{12,12,1}}; int[]c={1,2,5,4,3}; int[]d=New int[5]; //traversing array a     for(int[] is:a) { for(intI:is) {System.out.print (i+" "); }            }    //to sort the C arrayArrays.sort (c);  for(inti = 0; i < c.length; i++) {System.out.print (C[i]+"  ");        } System.out.println (); //comparison of two arraysSystem.out.println (Arrays.equals (A, b)); //array for numeric lookupSystem.out.println (Arrays.binarysearch (C, 4)); //Array ReplicationSystem.arraycopy (c, 1, D, 1, 4);  for(inti:d) {System.out.print (i+"  ");        } System.out.println (); //array paddingArrays.fill (d, 0, 1, 1);  for(inti:d) {System.out.print (i+"  "); }      }}

Operation Result:

1 2 3 4 8 5 7 6 1  2  3  4  5  false2  3 4 5 1 2 3  4  5  

Note: Some of these methods are valid only for one-dimensional arrays

Related knowledge of arrays