#include <cstdio>
using namespace std;
int sumN(int x) {
    int ans = 0;
    while (x >= 1) {
        ans += x % 10;
        x /= 10;
    }
    return ans;
}
int main() {
    int num;
    long long ans = 0;
    int sumNum[47] = { 0 };
    scanf("%d", &num);
    for (int i = 1; i <= num; i++) {
        sumNum[sumN(i)]++;
    }
    for (int i = 1; i < 46; i++) {
        ans += sumNum[i] * sumNum[i];
    }
    printf("%lld", ans);
    return 0;
}