grayCode.cpp

#include <stack>
#include <string>
#include <iostream>
#include <stdio.h>
#include <stdlib.h>

using namespace std;

stack<string> addBit(stack<string> ori);
void generating(stack<string> ori, stack<string> *n);

int main(int argc, char *argv[])
{
	stack<string> grayCode;
	int codeBit;
	// initial base grayCode
	grayCode.push("1");
	grayCode.push("0");

	cout << "Enter an integer n: ";
	cin >> codeBit;

	for(int i=1;i<codeBit;i++) grayCode = addBit(grayCode);
	
	cout << "The list of " << codeBit << "-bit Gray code is: ";

	while(!grayCode.empty()){
		cout << grayCode.top() << " ";
		grayCode.pop();
	}
	cout << endl;
	return 0;
}

stack<string> addBit(stack<string> ori){
	stack<string> n;
	generating(ori , &n);
	return n;
}

void generating(stack<string> ori, stack<string> *n){
	if(ori.empty()) return;
	string top = ori.top();
	ori.pop();
	n->push("1" + top);
	generating(ori, n);
	n->push("0" + top);
}