Deleting digits

#include <algorithm>
#include <iostream>
#include <queue>
#include <vector>
 
using namespace std;
 
 
int best(int x) {
 
    if (x == 0) return 0;
    else if (x < 0) return 1e9;
    //cout << x << endl;
 
    int y = x;
 
    
 
    int miny = 1e9;
    while (y != 0) {
       //cout << y << endl;
         if (y%10 != 0) miny = min(miny, best(x - (y%10)) + 1);
        y /= 10;
    }
 
    return miny;
}
 
 
int best2(int N)
{
    vector<int> dp(N + 1, 1e9);
 
    dp[0] = 0;
 
    for (int i = 0; i <= N; i++) {
        for (char c : to_string(i)) {
 
            dp[i] = min(dp[i],
                        dp[i - (c - '0')]
                            + 1);
        }
    }
    return dp[N];
}
 
 
int main() {
 
    int x;
    cin >> x;
 
    cout << best2(x) << endl;
 
 
}

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