```#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin >> n;
    vector<int>dp(n+1,INT_MAX-2);
    dp[0] = 0;
    for(int i =0;i<=n;i++)
        for(int j = 1;j*j<=i;j++)
            dp[i] =min(dp[i],dp[i-j*j]+1);
    cout<<dp[n];
    return 0;
}