Simple Text Encryption

/*
*	Author: Defcon Noob :)
*	July 20, 2011
*/

#include <iostream>
#include <Windows.h>
#include <string>
#include <time.h>
#include <vector>
#include <math.h>
#include <stdio.h>


using namespace std;
int random;
void encrypt( string &m, vector<int> &e); 
void decrypt( string &m, vector<int> &e);

int input;

int main( )
{
	string m;
	vector<int> e;
	int choice;
	int i=0;
		cout << "Input string: " << endl;
		getline(cin, m);
		while(1){
			cout << " " << endl;
			cout << "Enter 0 for encrypt, 1 for decrypt." << endl;
			cout << " " << endl;
			Sleep(500);
			cin >> choice;
			if (choice)
			{
				input=45;
				decrypt(m, e);
			}
			else
			{
				input=45;
				encrypt(m, e);
			}
			Sleep(5000);
		}
	system("pause");
	return 0;
}
void encrypt (string &m, vector<int> &e) 
{
	int size;
	size = m.size();
	for(int i=0; i < size; i++)
	{
		e.push_back((unsigned char)m[i] * input);
		m[i] = ' ';
	}
	cout << " " << endl;
	cout << "Encrypted string is: ";
	cout << " " << endl;
	for (int i = 0; i < e.size(); i++)
		cout << e[i];
	cout << endl;
}
void decrypt(string &m, vector<int> &e) 
{
	int size;
	size = m.size();
	for(int i=0; i < size; i++){
		m[i] = (unsigned char)(e[i] / input );
	}
	cout << " " << endl;
	cout << "Decrypted string is: " << m << endl;
	cout << " " << endl;
	
}