#include <bits/stdc++.h>
using namespace std;

const int N = 25, inf = 1 << 30;

int minv[N], mins[N];
int h[N], r[N];
int n, m, ans = 1 << 30;

void dfs(int dep, int v, int s) { // 处理完的体积和处理完的体积
    if(v + minv[dep] > n) return;
    if(s + mins[dep] >= ans) return;
    if(s + 2 * (n - v) / r[dep + 1] >= ans) return;
    if(!dep) {
        if(v == n) ans = s;
        return;
    }
    //枚举dep层了
    for(int R = min(r[dep + 1] - 1, (int)sqrt((n - v - minv[dep - 1]) / dep)); R >= dep; R -- )
        for(int H = min(h[dep + 1] - 1, (n - v - minv[dep - 1]) / R / R); H >= dep; H -- ){
            h[dep] = H, r[dep] = R;
            int t = dep == m ? R * R : 0;
            dfs(dep - 1, v + R * R * H, s + 2 * R * H + t);
        }
}

int main() {
    cin >> n >> m;
    for(int i = 1; i <= m; i ++ ) {
        minv[i] = minv[i - 1] + i * i * i;
        mins[i] = mins[i - 1] + i * i * 2;
    }
    h[m + 1] = r[m + 1] = inf;
    dfs(m, 0, 0);
    if(ans == inf) ans = 0;
    cout << ans << endl;
    return 0;
}