Java Novice Learning Notes--Array (iii): two-dimensional array __java

definition

1. Two-D array definition
//2. Two-d array of memory space
//3. Irregular array
package me.array;
public class array2demo{public
	
	
	static void Main (string[] args) {
		
		
		//define two-dimensional array
		int[] [] arr={{1,2,3},{4,5,6}};< c8/>//statically initializes
		 
		//prints out two-dimensional array for
		
		(int i=0;i<arr.length;i++) {for
			
			(int j=0;j<arr[i].length;j++) {
					
				System.out.print (arr[i][j]+ "");
				
			}
			Output a column after the carriage return space
			System.out.println ();}}
	

Two-dimensional array memory structure

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Irregular two-dimensional arrays

1. Two-D array definition
//2. Two-d array of memory space
//3. Irregular array
package me.array;
public class array2demo{public
	
	
	static void Main (string[] args) {
		
		//create and print irregular two-dimensional array
		int arr[] [];
		
		Arr=new int[3][];//now indicates that an irregular array
		
		arr[0]=new int[10];//arr[0] points to another array
		arr[1]=new int[3];
		Arr[2]=new int[4];
		
		Assignment for
		(int i=0;i<arr.length;i++) {for
			
			(int j=0;j<arr[i].length;j++) {
				
				arr[i][j]=j}}
			
		}
		
		//output for
		(int i=0;i<arr.length;i++) {for
			
			(int j=0;j<arr[i].length;j++) {
				
				System.out.print (arr[i][j]+ "");
			}
			System.out.println ();
		}
		
		/* Output results: 0 1 2 3 4 5 6 7 8 9 0 1 2 0 1 2 3 
		*///
		
	}
	
}

3. Write a method that returns a double two-dimensional array, which is obtained by parsing string parameters.
such as "1,2;3,4,5;6,7,8"//d[0,0]=1.0 d[0,1]=2.0 d[1,0]=3.0 ... package me.parser; public class teststring{public static void Main (string[] args) {//1. Splitting split (";") with a string
		into three string array//2. Re-decompose split (",")//Declare a two-dimensional array to be used to load the decomposed character String s= "1,2;3,4,5;6,7,8";
		
		The split () method is used to decompose string[] Sfirst=s.split (";");
		
		String[][] Word=new string[sfirst.length][];
		int flag=0;
			for (int i=0;i<sfirst.length;i++) {//Print out separated//system.out.println (Sfirst[i]);
			 /* This statement outputs 1,2 3,4,5 6,7,8 *///next in accordance, separate them into a one-dimensional array string[] Ssecond=sfirst[i].split (",");
			~ System.out.println (ssecond.length);
			~//* Output://~ 2//~---------------------------------//~ 3//~---------------------------------//~ 3 ~---------------------------------//~ *///Description Each Ssencond the length of this one-dimensional array is different word[i]=new string[ssecond.length];//This step determines whether the row is not Each line length of the rule array is assigned to this array for (int j=0;j<ssecond.length;j++) {word[i][j]=SSECOND[J];
		System.out.println ("---------------This is the first" + (i+1) + "secondary cycle-------------------");
		}//Output two-dimensional array System.out.println ("Output two-dimensional array-------------------");
			for (int i=0;i<word.length;i++) {for (int j=0;j<word[i].length;j++) {System.out.print (word[i][j]+ "");
		} System.out.println (); }/* Result:---------------This is the 1th time loop----------------------------------This is the 2nd cycle----------------------------------This is the 3rd cycle -------------------output two-dimensional array-------------------1 2 3 4 5 6 7 8 output two-dimensional array-------------------*///}}

Author: Yanggan
Source: Http://blog.csdn.net/incyanggan
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