#include <bits/stdc++.h>   using namespace std;   int main() {     long long int n, k, i;     cin >> n >> k;     if (n % (2 * k + 1) == 0) {       cout << n / (2 * k + 1) <<   n ;       for (i = k + 1; i <= n; i += (2 * k + 1)) cout << i <<    ;     } else if (n % (2 * k + 1) < (k + 1)) {       cout << n / (2 * k + 1) + 1 <<   n ;       for (i = 1; i <= n; i += (2 * k + 1)) cout << i <<    ;     } else {       cout << n / (2 * k + 1) + 1 <<   n ;       for (i = k + 1; i <= n; i += (2 * k + 1)) cout << i <<    ;     }   }   