Repetition - Iteration

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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 }