#include <bits/stdc++.h>

using namespace std;

//求递增数组 11-10001之间的
bool IsDiZeng(int n) {
    int lastGe, ge = 10;
    while (n > 0) {
        lastGe = ge;
        ge = n % 10;
        n /= 10;
        if (ge > lastGe) return false;
    }
    return true;
}

int main() {
    int count = 0;
    for (int i = 12; i <= 10000; i++) {
        if (IsDiZeng(i)) {
            count++;
        }
    }
    cout << count << endl;
    return 0;
}