Java: Eighth chapter

Eighth Chapter Array

     1. Declaration Definitions for Arrays
data type [] Variable name = new data type [length];
Column: Int[]ary = new Int[5];
2. Value, Assignment
Value: Data name [subscript];
Column: int a = ary[1];
Assignment: variable = data name [subscript];
Column: ary[1]=10;
3. Iterating the array
The length of the array: array name. length;
for (int i=0;i< array name. length;i++) {
Array name [i]: Access value for each element
}
4. Common Exceptions for arrays
Array subscript out of bounds
ArrayIndexOutOfBoundsException
When the subscript of an array is accessed beyond 0~length-1, the
The above error will occur.
Note: array subscript range: 0~length-1
5. Common methods of arrays
Arrays.tostring (array name);//Display array contents
Arrays.sort (array name); Array in ascending order
6. Post-traversal
for (int i = ary.length-1;i>=0;i--) {
Ary[i]
}
7. Compare the size of a string
If A.compareignorecase (b) >0 is true,
So a>b.
If A.compareignorecase (b) <0 is true,
So a<b.
If A.compareignorecase (b) =0 is true,
So a=b.
8.break and Continue
Break: Terminate, End (indicates terminating the current loop structure)
Continue: Continue (indicates the end of this cycle, into the next cycle)
Note: Multi-layer loops only work on direct loops.

Example: Sorting an array after an inverse order Public Static voidMain (string[] args) {int[] AA =New int[]{1,3,-1,5,-2}; System. out. Print ("the original array is:");  for(intI=0; i<aa.length;i++) {System. out. Print (aa[i]+"\ t"); } System. out. println (""); System. out. Print ("the following arrays are processed in reverse order:");  for(intj = aa.length-1; j>=0; j--){            if(aa[j]<0) {Aa[j]=0; }system. out. Print ((aa[j]+"\ t")); }} Example: Inserting a value into an array Public Static voidMain (string[] args) {int[] ary =New int[6]; ary[0] = -; ary[1] = the; ary[2] = the; ary[3] = -; ary[4] = About; intindex =0; Scanner Console=NewScanner (System.inch); System. out. println ("Please enter a number:"); intnum =Console.nextint ();  for(inti =0; i<ary.length;i++){            if(ary[i]>num) {Index=i; System. out. println (Ary[i]);  Break; }        }         for(inti =4; i>=index;i--) {Ary[i+1] =Ary[i]; } Ary[index]=num; System. out. println (arrays.tostring (ary)); }

Java: Eighth chapter