平方求和

#include <iostream>
#include <algorithm>
#include<math.h>
#include <queue>
using namespace std;

bool is_sqrt(long long n)
{
    int m = sqrt(n);
    if (m*m == n)
        return true;
    else
        return false;
}

int solve(long long n)
{
    if (is_sqrt(n))
        return 1;
    while (n % 4 == 0)
        n /= 4;

    if (n % 8 == 7)
        return 4;

    for (int i = 0; i*i < n; i++)
    {
        if (is_sqrt(n - i*i))
            return 2;
    }
    return 3;
}

int main()
{
    long long n;
    while (cin>>n)
    {
        if (n == -1)
            break;
        cout<< solve(n)<<endl;

    }
    return 0;
}