using System;
public class Program
{
public static void Main()
const string alphabet = "abcdefghijklmnopqrstuvwxyz";
var rnd = new Random();
var ch1 = '\0';
var ch2 = '\0';
var aaaCount = 0;
var abcCount = 0;
var iteration = 0;
while (iteration++ < 1e7)
switch (alphabet[rnd.Next(0, alphabet.Length)])
case 'a':
if (ch1 == 'a')
if (ch2 == 'a')
aaaCount++;
}
else
ch2 = 'a';
continue;
ch1 = 'a';
break;
case 'b':
ch2 = 'b';
case 'c':
if (ch2 == 'b')
abcCount++;
ch1 = ch2 = '\0';
Console.WriteLine(@"aaa: {0}", aaaCount);
Console.WriteLine(@"abc: {0}", abcCount);