Deleting digits

#include <bits/stdc++.h>

using namespace std;

int n = 0;

int main() {
  // ios::sync_with_stdio(false);
  // cin.tie(0);
  cin >> n;

  int steps = 0;
  while(n !=0) {

    auto v = vector<int>();
    int temp = n;
    while(temp != 0) {
      v.push_back(temp % 10);
      temp /= 10;
    }

    auto a = max_element(v.begin(), v.end())[0];

    n -= a;

    steps++;
  }

  cout << steps;

  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED