#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000 * 1000 * 1000 + 7;
const long long INF = 1ll * 1000 * 1000 * 1000 * 1000 * 1000 * 1000 + 7;
const long long MOD2 = 998244353;
const long long N = 5000 * 100 + 1;
const long long N2 = 1000 * 1000 + 5;
const long double PI = 3.14159265;
const long long R = 250;
long long gcd(long long a, long long b) {
  if (!b) return a;
  return gcd(b, a % b);
}
long long power(long long x, long long y, long long p) {
  long long res = 1;
  x %= p;
  while (y > 0) {
    if (y & 1) res = (res * x) % p;
    y = y >> 1;
    x = (x * x) % p;
  }
  return res;
}
bool sortbysec(const pair<int, int> &a, const pair<int, int> &b) {
  return (a.second < b.second);
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n, k, i;
  int a[1000000];
  cin >> n >> k;
  for (i = 1; i <= 2 * n; i++) {
    a[i] = i;
  }
  int count = 0;
  for (i = 1; i <= 2 * n; i = i + 2) {
    swap(a[i], a[i + 1]);
    count++;
    if (count == k) {
      break;
    }
  }
  for (i = 1; i <= 2 * n; i++) {
    cout << a[i] << " ";
  }
  return 0;
}
