Submission #1439531

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Source Code Expand

#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <cmath>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <stdlib.h>
#include <stdio.h>
#include <bitset>
using namespace std;
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
typedef long long ll;

int main() {
  int N, x;
  cin >> N >> x;
  if(x == 1 || x == 2 * N - 1) {
    puts("No");
  } else {
    puts("Yes");
    if(N == 2) {
      FOR(i,0,3) cout << i + 1 << endl;
    } else {
      int num[2*N-1], ind[2*N];
      FOR(i,0,2*N-1) {
        num[i] = i + 1;
        ind[i+1] = i;
      }
      if(x == 2) {
        swap(num[(2*N-1)/2-1],num[ind[3]]);
        swap(ind[num[(2*N-1)/2-1]],ind[num[ind[3]]]);
        swap(num[(2*N-1)/2],num[ind[2]]);
        swap(ind[num[(2*N-1)/2]],ind[num[ind[2]]]);
        swap(num[(2*N-1)/2+1],num[ind[1]]);
        swap(ind[num[(2*N-1)/2+1]],ind[num[ind[1]]]);
        swap(num[(2*N-1)/2+2],num[ind[4]]);
        swap(ind[num[(2*N-1)/2+2]],ind[num[ind[4]]]);
      } else {
        swap(num[(2*N-1)/2-2],num[x-2]);
        swap(ind[num[(2*N-1)/2-2]],ind[num[ind[x-2]]]);
        swap(num[(2*N-1)/2-1],num[x]);
        swap(ind[num[(2*N-1)/2-1]],ind[num[ind[x]]]);
        swap(num[(2*N-1)/2],num[x-1]);
        swap(ind[num[(2*N-1)/2]],ind[num[ind[x-1]]]);
        swap(num[(2*N-1)/2+1],num[x-3]);
        swap(ind[num[(2*N-1)/2+1]],ind[num[ind[x-3]]]);
      }
      FOR(i,0,2*N-1) cout << num[i] << endl;
    }
  }
  return 0;
}

Submission Info

Judge Result