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#include <bits/stdc++.h>
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using namespace std;
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int main(){
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    ios::sync_with_stdio(false);
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    cin.tie(nullptr);
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    int x=0, i=0;
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    vector<long long> data;
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    cin >> x;
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    while (x!= 1){
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        //cout << x;
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        if (find(data.begin(), data.end(), x) != data.end()){
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            cout << x << "\n";
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            return 0;
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        }
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        else{
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            data.push_back(x);
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            int tmp = 0;
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            while(x != 0){
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                tmp += pow(x%10, 2);
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                x /= 10;
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                //cout << x << " " << tmp << " ";
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            }
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            i += 1;
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            x = tmp;
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            //cout << tmp;
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        }
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    }
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    cout << i << "\n";
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    return 0;
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}

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#include <bits/stdc++.h> // 引入所有函式庫
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using namespace std;
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bool is_in_history(long long number, vector<long long> history){
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    if (find(history.begin(), history.end(), number) != history.end()){
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        return true;
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    }
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    return false;
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}
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long long sum_of_digit_squares(long long number){
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    long long digit_square_sum = 0;
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    while(number != 0){
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        digit_square_sum += pow(number%10, 2);
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        number /= 10;
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    }
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    return digit_square_sum;
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}
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int main(){
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    ios::sync_with_stdio(false);
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    cin.tie(nullptr); // 這兩行代碼用於加速輸入的速度，避免TLE
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    long long input_number=0, step=0;
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    vector<long long> history;
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    cin >> input_number;
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    while (input_number != 1){
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        if (is_in_history(input_number, history)){
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            cout << input_number << "\n";
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            return 0;
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        }
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        else{
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            history.push_back(input_number);
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            input_number = sum_of_digit_squares(input_number);
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            step += 1;
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        }
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    }
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    cout << step << "\n";
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    return 0;
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}

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def is_in_history(number:int, history:list):
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    if number in history:
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        return True
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    else:
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        return False
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def sum_of_digit_squares(number:int):
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    digit_square_sum = 0
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    while number != 0:
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        digit_square_sum += (number%10)**2
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        number //= 10
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    return digit_square_sum
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def main():
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    input_number = int(input())
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    history = []
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    step = 0
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    while input_number != 1:
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        if is_in_history(input_number, history):
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            print(input_number)
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            return 0
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        else:
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            history.append(input_number)
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            input_number = sum_of_digit_squares(input_number)
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            step += 1
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    print(step)
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    return 0
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main()