C# Enumerable yield and foreach
The professor today asks us in the class to solve this exercise in C# can someone help me out i'm lost...
The purpose of this exercise and the next one is to emphasize the power of enumerables and the yield and foreach statements. Declare a generic static method Flatten that takes as argument an array of IEnumerable<T> and returns an IEnumerable<T> . Use foreach statements and the yield return statement. The method should have this header:
public static IEnumerable<T> Flatten<T>(IEnumerable<T>[] ebles) { ... }
If you call the method as shown below, you should get 2 3 5 7 2 3 5 7 2 3 5 7:
IEnumerable<int>[] ebles = new IEnumerable<int>[3];
ebles[0] = ebles[1] = ebles[2] = new int[] { 2, 3, 5, 7 };
foreach (int i in Flatten<int>(ebles))
Console.Write(i + " ");
You need two nested foreach loops. One iterates the ebles the inner one the elements in each list. The innermost loop contains a yield return element ;
This is the outline. Now go and read about each of the words mentioned in this outline.
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