Genetic.h:19: error: expected ‘,’ or ‘...’ before ‘>’ token

Genetic.h:19: error: wrong number of template arguments (1, should be 2)
/usr/lib/gcc/i486-linux-gnu/4.1.2/../../../../include/c++/4.1.2/bits/stl_pair.h:68: error: provided for ‘template<class _T1, class _T2> struct std::pair’

Genetic.h:19: error: default argument missing for parameter 4 of ‘GeneNode::GeneNode(GeneNode*, GeneNode*, std::pair<char, int>, int)’

make: *** [Genetic.o] Error 1


#ifndef GENETIC_H
#define GENETIC_H

#include <iostream>
#include <math.h>

using namespace std;


//TODO templates
struct GeneNode
{
	GeneNode* left;
	GeneNode* right;

	// represents operator and number (if char == 0 (in this case))
	pair<char, int> data;

	GeneNode(GeneNode* l = NULL, GeneNode* r = NULL, pair<char, int> ch = pair<char, int> (0,0)) : left (l), right(r), data(ch) {}
	
	virtual ~GeneNode();
	virtual void makeEmpty();

	virtual void print (ostream& out = cerr) const
	{
		if (left)
			left->print (out);
		
		out << data.first << ":" << data.second << ' ';
		
		if (right)
			right->print (out);
	}
};

//.... other class defs also (too lazy to create multiple files at the mo (prototype phase you see))