help with functions

[iceteap3]

hey guys i need to make this code into seprate functions, i have no idea where to start. help !!

Basically its a fourier graph program in which the user enters the number of interations and the program pumps out a graph .

#define _USE_MATH_DEFINES
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;

int main ()
{ 
	int not;
	double unrsum=0;
	const int asize =61;
	int rsum;
	double xy=40/M_PI;
	int arrayx[asize];
	int max=0;
	int min=0;

	cout << "FOURIER SERIES GRAPH\n";
	cout << "No. of terms = ";
	cin>>not;
	while (not<=0)

	{
		cout << "No. of terms must be greater than zero."<<endl;
		cout << "Enter No. of terms: ";
		cin>> not;
	}


	for(int theta=0;theta<=360;theta+=6)
	{
		for(int n=0;n<not;n++)
		{
			double thetarad;
			thetarad=theta*((M_PI)/180);
			unrsum+=((sin((2*n + 1)*((thetarad))))/(2*n + 1));;
		}
		if (unrsum > 0)
		{
			rsum = xy*unrsum + 0.5;
		}
		else
		{
			rsum = xy*unrsum - 0.5;
		}
		int r=theta/6;
		arrayx[r]=rsum;
		unrsum=0;
	}

	max = arrayx[0];
	for (int i = 1; i < asize; i++)
	{
		if (arrayx[i] > max)
		{
			max = arrayx[i];
		}
	}
	min =arrayx[0];
	for (int i = 1; i < asize; i++)
	{
		if (arrayx[i] < min)
		{
			min = arrayx[i];
		}
	}
	{ for(int i =max;i>=min;i--)

	{
		if (i==0)
		{
			cout <<setw(3)<<i << " ";

			for (int x=0;x<=asize;x++){

				if(i==arrayx[x])
				{
					cout << "*";
				}

				else
				{
					cout << "-";
				}
			}		
		}
		else
		{	cout <<setw(3)<<i<<" ";

		for (int x=0;x<=asize;x++){

			if(i==arrayx[x])
			{
				cout << "*";
			}

			else
			{	
				cout << " ";
			}
		}

		}
		cout <<endl;
	}

	}
}

thanks so much !