fork download
copy 
  1. #include<bits/stdc++.h>
  2.  
  3. #define ll long long
  4. #define pp push_back
  5. #define endl '\n'
  6. #define all(x) x.begin(),x.end()
  7. #define ld long double
  8. #define PI acos(-1)
  9. #define ones(x) __builtin_popcountll(x)
  10. //#define int ll
  11.  
  12. using namespace std;
  13.  
  14. void Drakon() {
  15.     ios_base::sync_with_stdio(false);
  16.     cin.tie(nullptr);
  17.     cout.tie(nullptr);
  18. #ifdef Clion
  19.     freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
  20. #endif
  21. }
  22.  
  23. unsigned long long inf = 1e10;
  24. const double EPS = 1e-6;
  25. const int MOD = 1000000007, N = 200005, LOG = 25;
  26.  
  27. ll mul(const ll &a, const ll &b) {
  28.     return (a % MOD + MOD) * (b % MOD + MOD) % MOD;
  29. }
  30.  
  31. ll add(const ll &a, const ll &b) {
  32.     return (a + b + 2 * MOD) % MOD;
  33. }
  34.  
  35. ll pw(ll x, ll y) {
  36.     ll ret = 1;
  37.     while (y > 0) {
  38.         if (y % 2 == 0) {
  39.             x = mul(x, x);
  40.             y = y / 2;
  41.         } else {
  42.             ret = mul(ret, x);
  43.             y = y - 1;
  44.         }
  45.     }
  46.     return ret;
  47. }
  48.  
  49. set<vector<vector<int>>> s;
  50. int n;
  51. vector<pair<int, int>> bestMoves;
  52.  
  53. void slv(vector<vector<int>> tower, vector<pair<int, int>> moves) {
  54.     if(tower.back().size() == n) {
  55.         if(moves.size() < bestMoves.size() || bestMoves.empty()) bestMoves = moves;
  56.         return;
  57.     }
  58.     if(s.count(tower)) return;
  59.     s.insert(tower);
  60.     for(int i = 0; i < 3; ++i) {
  61.         for(int j = 0; j < 3; ++j) {
  62.             if(i == j || tower[i].empty()) continue;
  63.             int back = tower[i].back();
  64.             if(tower[j].empty() || back < tower[j].back()) {
  65.                 tower[j].push_back(back);
  66.                 tower[i].pop_back();
  67.                 moves.push_back({i + 1, j + 1});
  68.  
  69.                 slv(tower, moves);
  70.  
  71.                 tower[j].pop_back();
  72.                 tower[i].push_back(back);
  73.                 moves.pop_back();
  74.             }
  75.         }
  76.     }
  77. }
  78.  
  79. void solve() {
  80.     cin >> n;
  81.     vector<vector<int>> tower = vector<vector<int>>(3);
  82.     for (int i = n; i >= 1; --i) {
  83.         tower[0].push_back(i);
  84.     }
  85.     slv(tower, {});
  86.     cout << bestMoves.size() << endl;
  87.     for(auto &[x, y] : bestMoves) cout << x << ' ' << y << endl;
  88. }
  89.  
  90. signed main() {
  91.     Drakon();
  92.     int t = 1;
  93.     //cin >> t;
  94.     while (t--) {
  95.         solve();
  96.     }
  97. }
Success #stdin #stdout 0.01s 5324KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
0
https://ideone.com/iSpr4q
language:
C++14 (gcc 8.3)
created:
6 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!