Even Simple

 

using System;

class NormalDistribution {

static Random rand = new Random();

// returns a normally distributed random number in the range [0..1[
static double NextNormal() {
double x = 0;
for (int i = 0; i < 5; i++) x += rand.NextDouble();
return x / 5;
}

static void Main(string[] arg) {
int[] tab = new int[20];
// fill tab
for (int i = 0; i < 200; i++) tab[(int)(20 * NextNormal())]++;
// print tab as a histogram
for (int i = 0; i < 20; i++) {
Console.Write("{0,2}: ", i);
for (int j = 0; j < tab[i]; j++) Console.Write("*");
Console.WriteLine();
}
}
}