I am getting below run time error in Codeforces, though code works as expected in my local compiler. Time: 0 ms, memory: 0 KB Verdict: RUNTIME_ERROR

I submitted my code for http://codeforces.com/contest/317/problem/A

Code is below.

#include <iostream>
using namespace std;

int main(){
	double a,b,n;
	cin >> a >> b >> n;
	
	int minop=0;
	while(true){
		if((a >= n) || (b >= n)) 
			break;
		else {
			if(a<=0 || b <=0)
				break;
			minop++;
			if(a>b)
				b=a+b;
			else
				a=a+b;
		}
	}
	
	if(minop==0) minop=-1;
	cout << minop;
	
	return 1;	
}

Unable to understand the error. Please suggest how to solve it.