Difference between revisions of "Concatenating arrays"

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(spacing consistency, grammar, punct.)
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{{1010PrAD|ProblemName=Create a Grocery List
 
{{1010PrAD|ProblemName=Create a Grocery List
  
|Problem=Given an array of strings join the strings together to create a single string.
+
|Problem=Join an array of strings together to create a single string.
  
Example Output<br>
+
Example:<br>
 
<pre>
 
<pre>
String[] strings = { "First string is short.",  
+
String[] strings = { "First ",  
                     "Second string is a bit longer",  
+
                     "Second ",  
                     "Third sting is even more longererer" };
+
                     "Third" };
 +
</pre>
 +
Would have output:
 +
<pre>
 +
"First Second Third"
 
</pre>
 
</pre>
 
|SideSectionTitle=More with Arrays
 
|SideSectionTitle=More with Arrays
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|Solution=
 
|Solution=
  
There are multiple ways of joining the strings together. The simplest way, using +,  you are probably already familiar with.
+
There are multiple ways of joining strings together. The simplest way is to use the plus symbol, which you are probably familiar with.
 
<pre>
 
<pre>
 
for( int i = 0; i < strings.length; i++ )
 
for( int i = 0; i < strings.length; i++ )
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+
The String class also offers the method concat() to concatenate strings.
The String class also offer the method, concat, to concatenate strings
+
 
<pre>
 
<pre>
 
for( int i = 0; i < strings.length; i++ )
 
for( int i = 0; i < strings.length; i++ )
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+
Java also offers the StringBuilder class which is best used when building up larger strings.
Java also offers the StringBuilder class which is best used when building up larger strings
+
 
<pre>
 
<pre>
 
for( int i = 0; i < strings.length; i++ )
 
for( int i = 0; i < strings.length; i++ )
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|SolutionCode=
 
|SolutionCode=
  
public class stringTests {
+
public class stringTests
 
+
{
 
public static void main(String[] args)
 
public static void main(String[] args)
 
{
 
{
Line 66: Line 68:
 
String tempString3 = new String();
 
String tempString3 = new String();
 
 
String[] strings = { "First string is short.",  
+
String[] strings = { "First ",  
                "Second string is a bit longer",  
+
                                    "Second ",  
                "Third sting is even more longererer" };
+
                                    "Third" };
 
 
 
for( int i = 0; i < strings.length; i++ )
 
for( int i = 0; i < strings.length; i++ )

Revision as of 11:21, 9 April 2010

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Problem

Join an array of strings together to create a single string.

Example:

String[] strings = { "First ", 
                     "Second ", 
                     "Third" };

Would have output:

"First Second Third"
 

More with Arrays

Wiki method01.jpg


Solution

There are multiple ways of joining strings together. The simplest way is to use the plus symbol, which you are probably familiar with.

for( int i = 0; i < strings.length; i++ )
{
	tempString1 = tempString1 + strings[i];
}
System.out.println( "1. " + tempString1 );


The String class also offers the method concat() to concatenate strings.

for( int i = 0; i < strings.length; i++ )
{
	tempString2 = tempString2.concat( strings[i] );
}
System.out.println( "2. " + tempString2 );


Java also offers the StringBuilder class which is best used when building up larger strings.

for( int i = 0; i < strings.length; i++ )
{
	sb.append( strings[i] );
}
tempString3 = sb.toString();
System.out.println( "3. " + tempString3 );

Code

Solution Code

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