Finding the Largest Multiple of 10 that is Less than or equal to n using C++

#include <bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    int digits = 0;
    while (n > 0) {
        n /= 10;
        digits++;
    }
    cout << pow(10, digits - 1) << '\n';
    return 0;
}