#include <bits/stdc++.h>   using namespace std;   int main() {     int n, k;     scanf( %d%d , &n, &k);     int width = 2 * k + 1;     if (width >= n) {       printf( 1 n );       printf( %d , n / 2 + n % 2);       return 0;     }     if (n % width == 0) {       printf( %d n , n / width);       for (int out = k + 1; out <= n; out += width) {         printf( %d  , out);       }       return 0;     }     vector<int> v;     for (int i = 1, rest; i <= k; ++i) {       rest = n - i - k;       if (rest % width > k || rest % width == 0) {         for (int out = i; out <= n; out += width) {           v.push_back(out);         }         break;       }     }     printf( %d n , v.size());     for (int i = 0; i < v.size(); ++i) {       printf( %d  , v[i]);     }   }   