func_code_string: #include <bits/stdc++.h>   using namespace std;   char moves[4] = { L ,  U ,  R ,  D };   long long dx[4] = {-1, 0, 1, 0};   long long dy[4] = {0, -1, 0, 1};   const long long N = 1e3 + 1;   bool visited[N];   vector<long long> adj[N];   long long n, k;   signed main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     cin >> n >> k;     for (long long i = 1; i < k + 1; i++) {       cout << 2 * i <<     << 2 * i - 1 <<    ;     }     for (long long i = 2 * k + 1; i < 2 * n + 1; i++) cout << i <<    ;     return 0;   }   