#include <bits/stdc++.h>
using namespace std;

long long n, m;

int main()
{
	cin >> n;

	m = n;

	for (int j = 2; j <= log2(n); j++) {
		long long i = (long long)pow(n, 1 / (double)j), u = pow(i, j);

		if (i + j + n - u < n) {
			m = min(m, i + j + n - u);
		}
	}

	cout << m << endl;
}