One Based Arithmetic

#include <bits/stdc++.h>
typedef long long ll;
typedef unsigned long long ull;
#define pb push_back
#define vll vector<ll>
#define vi vector<int>
#define tests int t; cin >> t; while(t--)
using namespace std;

vll a(18);

ll dfs(ll n, ll k) {
    ll m = n/a[k];
    n = n%a[k];
    if(n == 0) return m*k;
    return m*k+min(k+dfs(a[k]-n, k-1), dfs(n, k-1));
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
    ll n; cin >> n;
    a[0] = 0;
    for(int i = 1; i < 18; i++) {
        a[i] = a[i-1]*10LL+1;
    }
    cout << dfs(n, 17);
    return 0;
}