import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args) {
        final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        try {
            int T = 1;
            for (int i = 0; i < T; ++i) {
                Runner runner = new Runner(br, bw);
                runner.run();
                runner.flush();
            }
            br.close();
            bw.close();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}

class Solution {
    final int n;
    final int[] dp;

    Solution(int n) {
        this.n = n;
        this.dp = new int[n + 1];
    }

    int solution() {
        for (int i = 1; i <= n; ++i) {
            int ans = Integer.MAX_VALUE;
            for (int j = 1; j * j <= i; ++j) {
                ans = Math.min(ans, dp[i - j * j] + 1);
            }
            dp[i] = ans;
        }
        return dp[n];
    }
}

class Runner {
    final Reader reader;
    final BufferedWriter bw;

    final int n;

    Runner(BufferedReader br, BufferedWriter bw) {
        this.reader = new Reader(br);
        this.bw = bw;
        try {
            this.n = Integer.parseInt(br.readLine());

        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    public void flush() {
        try {
            bw.write('\n');
            bw.flush();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    public void run() throws IOException {
        var sol = new Solution(n);
        var res = sol.solution();
        bw.write(String.valueOf(res));
    }
}

class Reader {
    private BufferedReader br;

    public Reader(BufferedReader br) {
        this.br = br;
    }
}