Sort words and numbers

Sort

using System;
using System.Collections.Generic;

// Given a string containing a combination of words and numbers, sort the string
// such that the words and numbers maintain their position in the string

// Input:  car 2 bus 1
// Output: bus 1 car 2

namespace SortWordsAndNumbers
{
    public class Program
    {
        public static void Main(string[] args)
        {
            test("car 2 bus 1");
            test("zebra 5 8 9 ace boo 2");
        }
        
        static void test(string s) {
            Console.WriteLine("Input: {0}", s);
            Console.WriteLine("Output: {0}", sort(s));
        }
        
        static string sort(string input) {
            if (String.IsNullOrEmpty(input)) {
                return input;
            }
            
            var inputs = input.Split(' ');
            
            var strings = new List<string>();
            
            var numbers = new List<int>();
            
            var stringMap = new bool[inputs.Length];
            
            for (int i = 0; i < inputs.Length; i++) {
                int result = 0;
                if (Int32.TryParse(inputs[i], out result)) {
                    numbers.Add(result);
                } else {
                    strings.Add(inputs[i]);
                    stringMap[i] = true;
                }
            }
            
            strings.Sort();
            
            numbers.Sort();
            
            int p = 0;
            int q = 0;
            
            var output = new string[inputs.Length];
            int current = 0;
            
            while (current < output.Length) {
                if (stringMap[current]) {
                    output[current++] = strings[p++];
                } else {
                    output[current++] = numbers[q++].ToString();
                }
            }
            
            return String.Join(" ", output);
        }
    }
}