#include <bits/stdc++.h> #define pb push_back using namespace std; typedef long long ll; struct Node { ll val; Node *next; Node(ll v) : val(v) { next = NULL; } }; ll counterList(vector<ll> &v, ll k) { if(v[0] > v[v.size() - 1]) return 0; Node *root = NULL; for(int i = v.size() - 1; i >= 0; i--) { Node *pom = new Node(v[i]); pom->next = root; root = pom; } Node *pom = new Node(0); pom->next = root; root = pom; ll del = 0, c = 0; while(del + 1 < v.size()) { Node *prev = root, *current = root->next; ll pr = 0; while(current != NULL) { if(current->val < pr || (current->next != NULL && current->val < current->next->val)) { prev->next = current->next; pr = current->val; Node *de = current; current = current->next; del++; delete de; } else { prev = current; pr = current->val; current = current->next; } } c++; } return c; } ll counter(vector<ll> v, ll k) { if(v[0] > v[v.size() - 1]) return 0; vector<ll> v2; ll c = 0; while(v.size() > 1) { for(int i = 0 ; i < v.size(); i++) { if(i == 0 && v[i] > v[i+1]){ v2.pb(v[i]); } else if(i == v.size()-1 && v[i] > v[i-1]) { v2.pb(v[i]); } else if(i-1 >= 0 && i+1 < v.size() && v[i] > v[i-1] && v[i] > v[i+1]) { v2.pb(v[i]); } } v = v2; v2.clear(); c++; if(c > k) return 0; } return c; } int main() { ios_base::sync_with_stdio(0); vector<ll> v; ll n, k, mod; cin >> n >> k >> mod; for (int i = 0; i < n; i++) v.pb(i+1); ll c = 0; do { if(counterList(v, k) == k) c = (c + 1) % mod; } while (next_permutation(v.begin(), v.end())); cout << (2*c)%mod; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 | #include <bits/stdc++.h> #define pb push_back using namespace std; typedef long long ll; struct Node { ll val; Node *next; Node(ll v) : val(v) { next = NULL; } }; ll counterList(vector<ll> &v, ll k) { if(v[0] > v[v.size() - 1]) return 0; Node *root = NULL; for(int i = v.size() - 1; i >= 0; i--) { Node *pom = new Node(v[i]); pom->next = root; root = pom; } Node *pom = new Node(0); pom->next = root; root = pom; ll del = 0, c = 0; while(del + 1 < v.size()) { Node *prev = root, *current = root->next; ll pr = 0; while(current != NULL) { if(current->val < pr || (current->next != NULL && current->val < current->next->val)) { prev->next = current->next; pr = current->val; Node *de = current; current = current->next; del++; delete de; } else { prev = current; pr = current->val; current = current->next; } } c++; } return c; } ll counter(vector<ll> v, ll k) { if(v[0] > v[v.size() - 1]) return 0; vector<ll> v2; ll c = 0; while(v.size() > 1) { for(int i = 0 ; i < v.size(); i++) { if(i == 0 && v[i] > v[i+1]){ v2.pb(v[i]); } else if(i == v.size()-1 && v[i] > v[i-1]) { v2.pb(v[i]); } else if(i-1 >= 0 && i+1 < v.size() && v[i] > v[i-1] && v[i] > v[i+1]) { v2.pb(v[i]); } } v = v2; v2.clear(); c++; if(c > k) return 0; } return c; } int main() { ios_base::sync_with_stdio(0); vector<ll> v; ll n, k, mod; cin >> n >> k >> mod; for (int i = 0; i < n; i++) v.pb(i+1); ll c = 0; do { if(counterList(v, k) == k) c = (c + 1) % mod; } while (next_permutation(v.begin(), v.end())); cout << (2*c)%mod; } |