Merge pull request #67 from TanujRohilla/master

Adding Radix Sort

Sorting/Radix Sort/RadixSort.cpp

@@ -0,0 +1,73 @@
+#include <iostream>
+
+using namespace std;
+
+// Get maximum value from array.
+int getMax(int arr[], int n)
+{
+	int max = arr[0];
+	for (int i = 1; i < n; i++)
+		if (arr[i] > max)
+			max = arr[i];
+	return max;
+}
+
+// Count sort of arr[].
+void countSort(int arr[], int n, int exp)
+{
+	// Count[i] array will be counting the number of array values having that 'i' digit at their (exp)th place.
+	int output[n], i, count[10] = {0};
+
+	// Count the number of times each digit occurred at (exp)th place in every input.
+	for (i = 0; i < n; i++)
+		count[(arr[i] / exp) % 10]++;
+
+	// Calculating their cumulative count.
+	for (i = 1; i < 10; i++)
+		count[i] += count[i-1];
+
+	// Inserting values according to the digit '(arr[i] / exp) % 10' fetched into count[(arr[i] / exp) % 10].
+	for (i = n - 1; i >= 0; i--)
+	{
+		output[count[(arr[i] / exp) % 10] - 1] = arr[i];
+		count[(arr[i] / exp) % 10]--;
+	}
+
+	// Assigning the result to the arr pointer of main().
+	for (i = 0; i < n; i++)
+		arr[i] = output[i];
+}
+
+// Sort arr[] of size n using Radix Sort.
+void radixsort(int arr[], int n)
+{
+	int exp, m;
+	m = getMax(arr, n);
+
+	// Calling countSort() for digit at (exp)th place in every input.
+	for (exp = 1; m/exp > 0; exp *= 10)
+		countSort(arr, n, exp);
+}
+
+int main()
+{
+	int n, i;
+	cout<<"\nEnter the number of data element to be sorted: ";
+	cin>>n;
+
+	int arr[n];
+	for(i = 0; i < n; i++)
+	{
+		cout<<"Enter element "<<i+1<<": ";
+		cin>>arr[i];
+	}
+
+	radixsort(arr, n);
+
+	// Printing the sorted data.
+	cout<<"\nSorted Data ";
+	for (i = 0; i < n; i++)
+		cout<<arr[i]<<" ";
+	return 0;
+}
+