Code:
#include <iostream>
#include <fstream>

using namespace std;

int prime [10000];
int index = 0, min, max;

bool isPrime(int x);
void genPal(int num, int add, int mulleft, int mulright);

int main(){
	ifstream fin ("pprime.in");
	ofstream fout ("pprime.out");
	fin >> min >> max;
	int max2 = max;
	int length;
	for(length = 0; max2; length++){
		max2 /= 10;
	}
	cout << length << '\n';
}

bool isPrime(int x){
	if(x < min || x > max || x%2 == 0 || x%3 == 0)
		return false; 
	for(int i = 2; i*i < x; i++)
		if(x%i == 0)
			return 0;
	return true;
}

void genPal(int num, int add, int mulleft, int mulright){
	int i, nmulleft, nmulright;
	if(num == 2)
		for(i = 0; i < 10; i++)
			 add+mulleft * i + mulright * i << '\n'; 
	else if(num == 1)
		for(i = 0; i < 10; i++)
			cout << add + mulright * i << '\n';
	else{
		nmulleft = mulleft / 10;
		nmulright = mulright * 10;
		num -= 2;
		for(i = 0; i < 10; i++)
			genPal(num, add+i*mulleft + i*mulright, nmulleft, nmulright);
	}
}
The errors:
test.cpp: In function 'int main()':
test.cpp:15: error 'min' undeclared(first use in this function)
and others like this. How do I fix this without making the variable min local to the main method?