Difference between revisions of "Repetition - Iteration"

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=Repetition=
 
Repetition is the use of a for loop to execute one piece of code over and over.
 
Repetition is the use of a for loop to execute one piece of code over and over.
 
There are multiple ways to create a for loop though. These are:
 
There are multiple ways to create a for loop though. These are:
* while uses one condition that which if met, will repeat the code.
+
 
<syntaxhighlight lang="csharp" line>             while (true)
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'''While''' uses one condition that which if met, will repeat the code.
                {
+
<syntaxhighlight lang="csharp" line>while (true)
                  x ++
+
  {
                }</syntaxhighlight>
+
    x ++;
 +
  }</syntaxhighlight>
 +
 
 +
'''For''' loops intialise a variable, check a condition and perform an action. This is done before each iteration.
 +
<syntaxhighlight lang="csharp" line>for (int i = 0; i <= 1000000; i++)
 +
  {
 +
    console.WriteLine(i);
 +
  }</syntaxhighlight>
 +
 
 +
'''Do while''' is the same as a while, however it doesn't check until it has done one iteration.
 +
<syntaxhighlight lang="csharp" line>do
 +
  {
 +
    x ++;
 +
  }
 +
while (true)</syntaxhighlight>
 +
 
 +
'''Foreach''' loops can also be used to access array variables [http://compsci.duckdns.org/mediawiki/index.php/Arrays]
 +
<syntaxhighlight lang="csharp" line>foreach (int x in Arr)
 +
  {
 +
    Console.WriteLine(x);
 +
  }</syntaxhighlight>
 +
 
 +
=Iteration=
 +
An iteration is the piece of code performed each time a loop runs.
 +
 
 +
Iterations can be skipped by calling the '''continue''' function.
 +
 
 +
<syntaxhighlight lang="csharp" line>
 +
for (int i = 0; i <= 10; i++)
 +
{
 +
    if(i==5)
 +
    {
 +
        continue;
 +
    }   
 +
    console.WriteLine(i);
 +
}</syntaxhighlight>
 +
 
 +
Iteration can be terminated with the '''break''' function.
 +
 
 +
<syntaxhighlight lang="csharp" line>
 +
for (int i = 0; i <= 10; i++)
 +
{
 +
    if(i==5)
 +
    {
 +
        break;
 +
    }   
 +
    console.WriteLine(i);
 +
}</syntaxhighlight>

Latest revision as of 13:20, 29 June 2018

Repetition

Repetition is the use of a for loop to execute one piece of code over and over. There are multiple ways to create a for loop though. These are:

While uses one condition that which if met, will repeat the code.

1 while (true)
2   {
3     x ++;
4   }

For loops intialise a variable, check a condition and perform an action. This is done before each iteration.

1 for (int i = 0; i <= 1000000; i++)
2   {
3     console.WriteLine(i);
4   }

Do while is the same as a while, however it doesn't check until it has done one iteration.

1 do 
2   {
3     x ++;
4   }
5 while (true)

Foreach loops can also be used to access array variables [1]

1 foreach (int x in Arr) 
2   {
3     Console.WriteLine(x);
4   }

Iteration

An iteration is the piece of code performed each time a loop runs.

Iterations can be skipped by calling the continue function.

1 for (int i = 0; i <= 10; i++)
2 {
3     if(i==5)
4     {
5          continue;
6     }    
7     console.WriteLine(i);
8 }

Iteration can be terminated with the break function.

1 for (int i = 0; i <= 10; i++)
2 {
3     if(i==5)
4     {
5          break;
6     }    
7     console.WriteLine(i);
8 }