#include <bits/stdc++.h>
using namespace std;
int toInt(string s) {
  istringstream sin(s);
  int t;
  sin >> t;
  return t;
}
template <class T>
string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}
long long toInt64(string s) {
  istringstream sin(s);
  long long t;
  sin >> t;
  return t;
}
template <class T>
T gcd(T a, T b) {
  if (a < 0) return gcd(-a, b);
  if (b < 0) return gcd(a, -b);
  return (b == 0) ? a : gcd(b, a % b);
}
long long C(long long n, long long m) {
  long long a[100], b[100];
  if (n < m) return 0;
  if (m == 0) return 1;
  if (m == 1) return n;
  for (int i = 1; i <= m; i++) {
    a[i] = n - i + 1;
    b[i] = i;
  }
  long long ans = 1;
  for (int i = 1; i <= m; i++) {
    for (int j = 1; j <= m; j++) {
      long long s = gcd(a[i], b[j]);
      if (s > 1) {
        a[i] /= s;
        b[j] /= s;
      }
    }
    ans *= a[i];
  }
  return ans;
}
const int N = 105;
struct node {
  int x, p;
} p[N];
bool cmp(const node &a, const node &b) { return a.x < b.x; }
int d[1000005];
int main() {
  int n, k;
  cin >> n >> k;
  for (int i = 1; i <= n; i++) {
    d[i * 2 - 1] = i * 2;
    d[i * 2] = i * 2 - 1;
  }
  for (int i = 1; i <= k; i++) {
    int t = d[i * 2 - 1];
    d[i * 2 - 1] = d[i * 2];
    d[i * 2] = t;
  }
  for (int i = 1; i <= n * 2; i++)
    if (i > 1)
      cout << " " << d[i];
    else
      cout << d[i];
  cout << endl;
  return 0;
}
