chore(CSharp): added radix sort

algorithms/CSharp/src/Sorts/radix-sort.cs

@@ -0,0 +1,81 @@
+using System;
+
+class myProgram {
+	public static int getMax(int[] arr, int n)
+	{
+		int mx = arr[0];
+		for (int i = 1; i < n; i++)
+			if (arr[i] > mx)
+				mx = arr[i];
+		return mx;
+	}
+
+	// A function to do counting sort of arr[] according to
+	// the digit represented by exp.
+	public static void countSort(int[] arr, int n, int exp)
+	{
+		int[] output = new int[n]; // output array
+		int i;
+		int[] count = new int[10];
+
+		// initializing all elements of count to 0
+		for (i = 0; i < 10; i++)
+			count[i] = 0;
+
+		// Store count of occurrences in count[]
+		for (i = 0; i < n; i++)
+			count[(arr[i] / exp) % 10]++;
+
+		// Change count[i] so that count[i] now contains
+		// actual
+		// position of this digit in output[]
+		for (i = 1; i < 10; i++)
+			count[i] += count[i - 1];
+
+		// Build the output array
+		for (i = n - 1; i >= 0; i--) {
+			output[count[(arr[i] / exp) % 10] - 1] = arr[i];
+			count[(arr[i] / exp) % 10]--;
+		}
+
+		// Copy the output array to arr[], so that arr[] now
+		// contains sorted numbers according to current
+		// digit
+		for (i = 0; i < n; i++)
+			arr[i] = output[i];
+	}
+
+	// The main function to that sorts arr[] of size n using
+	// Radix Sort
+	public static void radixsort(int[] arr, int n)
+	{
+		// Find the maximum number to know number of digits
+		int m = getMax(arr, n);
+
+		// Do counting sort for every digit. Note that
+		// instead of passing digit number, exp is passed.
+		// exp is 10^i where i is current digit number
+		for (int exp = 1; m / exp > 0; exp *= 10)
+			countSort(arr, n, exp);
+	}
+
+	// A utility function to print an array
+	public static void print(int[] arr, int n)
+	{
+		for (int i = 0; i < n; i++)
+			Console.Write(arr[i] + " ");
+	}
+
+	// Driver Code
+	public static void Main()
+	{
+		int[] arr = { 170, 45, 75, 90, 802, 24, 2, 66 };
+		int n = arr.Length;
+
+		// Function Call
+		radixsort(arr, n);
+		print(arr, n);
+	}
+
+	
+}