[CSES] Removing Digits

void solve()
{
    ll n;
    cin >> n;

    vll dp(n + 1, inf);
    dp[0] = 0;

    FOR(i, 1, n)
    {
        ll x = i;
        while (x)
        {
            ll d = x % 10;
            x /= 10;
            if (i - d >= 0)
            {
                dp[i] = min(dp[i], 1 + dp[i - d]);
            }
        }
    }

    cout << dp[n] << "\n";
}