Submission #1034473

#	Time	Username	Problem	Language	Result	Execution time	Memory
1034473		pera	Birthday gift (IZhO18_treearray)	C++17	100 / 100	664 ms	75740 KiB

treearray

#include<bits/stdc++.h>
using namespace std;
const int N = 2e5 + 1 , LOG = 18;
int n , m , q , a[N] , d[N] , LCA[N] , up[N][LOG];
vector<int> g[N];
set<int> E[N] , O[N];
void dfs(int u , int p = 1){
   up[u][0] = p;
   d[u] = d[p] + 1;
   for(int x = 0;x < (int)g[u].size();x ++){
      if(g[u][x] != p){
         dfs(g[u][x] , u);
      }
   }
}
int lca(int u , int v){
   if(d[u] < d[v]){
      swap(u , v);
   }
   int s = d[u] - d[v];
   for(int bit = 0;bit < LOG;bit ++){
      if(s >> bit & 1){
         u = up[u][bit];
      }
   }
   if(u == v){
      return u;
   }
   for(int bit = LOG - 1;bit >= 0;bit --){
      if(up[u][bit] != up[v][bit]){
         u = up[u][bit];
         v = up[v][bit];
      }
   }
   return up[u][0];
}
int main(){
   ios_base::sync_with_stdio(false);
   cin.tie(0);
   cout.tie(0);
   cin >> n >> m >> q;
   for(int x = 1;x < n;x ++){
      int u , v;
      cin >> u >> v;
      g[u].push_back(v);
      g[v].push_back(u);
   }
   dfs(1);
   for(int bit = 1;bit < LOG;bit ++){
      for(int x = 1;x <= n;x ++){
         up[x][bit] = up[up[x][bit - 1]][bit - 1];
      }
   }
   for(int x = 1;x <= m;x ++){
      cin >> a[x];
      E[a[x]].insert(x);
      if(x > 1){
         LCA[x - 1] = lca(a[x] , a[x - 1]);
         O[LCA[x - 1]].insert(x - 1);
      }
   }
   for(int i = 1;i <= q;i ++){
      int type;
      cin >> type;
      if(type == 1){
         int pos , v;
         cin >> pos >> v;
         E[a[pos]].erase(pos);
         if(pos < m){
            O[LCA[pos]].erase(pos);
         }
         if(pos > 1){
            O[LCA[pos - 1]].erase(pos - 1);
         }
         a[pos] = v;
         E[a[pos]].insert(pos);
         if(pos < m){
            LCA[pos] = lca(a[pos] , a[pos + 1]);
            O[LCA[pos]].insert(pos);
         }
         if(pos > 1){
            LCA[pos - 1] = lca(a[pos - 1] , a[pos]);
            O[LCA[pos - 1]].insert(pos - 1);
         }
      }else{
         int l , r , v;
         cin >> l >> r >> v;
         auto it = E[v].lower_bound(l);
         if(it != E[v].end() && *it <= r){
            cout << *it << " " << *it << endl;
            continue;
         }
         it = O[v].lower_bound(l);
         if(it != O[v].end() && *it < r){
            cout << *it << " " << *it + 1 << endl;
            continue;
         }
         cout << -1 << " " << -1 << endl;
      }
   }
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44