#include<iostream>
#include<stdio.h>
#include<algorithm>
#include<vector>
#include<string.h>
#include<math.h>
#include<map>
#include<iomanip>
#include<queue>

const long long mod=1e7;

using namespace std;

int main(){
	string s;
	cin >> s;
	long long n=0;
	for(int i=0;i<s.size();i++){
		n*=10;
		n+=s[i]-'0';
		n%=mod;
	}
	
	for(long long i=1;i<=n;i++){
		long long temp=(n+(i*i)%mod)%mod;
		long double temp2=sqrt(temp)+0.5;
		if((long long)(temp2*temp2)==temp){
			cout << 1 << endl;
			return 0;
		}
	}
	cout << -1 << endl;
	
	return 0;
}