test.d

import std.stdio;
import std.math;
import std.algorithm;
import std.string;
import std.conv;

void main()
{
	int[] arr;
	writeln("number of data");
	int n = readln.chomp.to!int;

	for(int i = 0; i < n; i++)
	{
		arr ~= readln.chomp.to!int;
	}

	arr.sort;

	auto avg = 0.0;
	foreach(e; arr)
	{
		avg += e;
	}
	avg /= n;

	auto mode = 0;
	{
		int maxmode = 0;
		int curmode = 0;
		for(int i = 1; i < n; i++)
		{
			if(arr[i] == arr[i - 1])
				curmode++;
			else
				curmode = 0;

			if(curmode > maxmode)
			{
				mode = arr[i];
				maxmode = curmode;
			}
		}
	}

	double median = (n % 2 == 0) ? ((arr[n / 2] + arr[n / 2 - 1]) / 2) : arr[n / 2];

	auto VR = 0.0;
	foreach(e; arr)
	{
		VR += pow(e, 2) / (n - 1);
	}
	auto SD = sqrt(VR);

	foreach(i, e; arr)
	{
		writeln(e, (i%5==4) ? '\n' : '\t');
	}

	writeln("average = ", avg);
	writeln("mode = ", mode);
	writeln("median = ", median);
	writeln("standard_deviation = ", SD);
}