oj.uz

Submission #1021311

# Submission time Handle Problem Language Result Execution time Memory
1021311 2024-07-12T16:50:42 Z huutuan Sorting (IOI15_sorting) C++14
74 / 100
 1000 ms 163756 KB 
#include "sorting.h"

#include <bits/stdc++.h>

using namespace std;

struct DSU{
   int cnt;
   vector<int> lab;
   vector<pair<int*, int>> changes;
   void init(int n){
      cnt=0;
      lab.assign(n, -1);
   }
   int find_set(int u){
      return lab[u]<0?u:find_set(lab[u]);
   }
   void union_sets(int u, int v){
      u=find_set(u); v=find_set(v);
      if (u!=v){
         if (lab[u]>lab[v]) swap(u, v);
         changes.emplace_back(&lab[u], lab[u]);
         changes.emplace_back(&lab[v], lab[v]);
         lab[u]+=lab[v];
         lab[v]=u;
         changes.emplace_back(&cnt, cnt);
         ++cnt;
      }
   }
   void rollback(int size){
      while ((int)changes.size()>size){
         *changes.back().first=changes.back().second;
         changes.pop_back();
      }
   }
} dsu;

struct SegmentTree{
   int n;
   vector<vector<pair<int, int>>> t;
   void init(int _n){
      n=_n;
      t.assign(4*n+1, {});
   }
   void update(int k, int l, int r, int L, int R, int u, int v){
      if (r<L || R<l) return;
      if (L<=l && r<=R){
         t[k].emplace_back(u, v);
         return;
      }
      int mid=(l+r)>>1;
      update(k<<1, l, mid, L, R, u, v);
      update(k<<1|1, mid+1, r, L, R, u, v);
   }
   int dfs(int k, int l, int r){
      int size=dsu.changes.size();
      for (auto &i:t[k]) dsu.union_sets(i.first, i.second);
      int ans=-1;
      if (l==r){
         if (dsu.cnt<=l) ans=l;
      }else{
         int mid=(l+r)>>1;
         if (ans==-1) ans=dfs(k<<1, l, mid);
         if (ans==-1) ans=dfs(k<<1|1, mid+1, r);
      }
      dsu.rollback(size);
      return ans;
   }
} st;

int a[200010], s[200010], pos[200010], pa[200010];

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
   dsu.init(N);
   st.init(M+1);
   map<pair<int, int>, int> mp;
   for (int i=0; i<N; ++i) s[i]=S[i], a[i]=i, mp[{s[i], a[i]}]=0, pa[i]=i;
   for (int i=0; i<M; ++i){
      if (X[i]!=Y[i]){
         int p1=pa[X[i]], p2=pa[Y[i]];
         st.update(1, 0, M, mp[{s[p1], a[p1]}], i, s[p1], a[p1]);
         mp.erase({s[p1], a[p1]});
         st.update(1, 0, M, mp[{s[p2], a[p2]}], i, s[p2], a[p2]);
         mp.erase({s[p2], a[p2]});
         swap(a[p1], a[p2]);
         pa[a[p1]]=p1;
         pa[a[p2]]=p2;
         mp[{s[p1], a[p1]}]=i+1;
         mp[{s[p2], a[p2]}]=i+1;
      }
   }
   for (auto &i:mp) st.update(1, 0, M-1, i.second, M, i.first.first, i.first.second);
   int ans=st.dfs(1, 0, M);
   if (ans==-1) return -1;
   for (int i=0; i<N; ++i) s[i]=S[i], a[i]=i, pos[s[i]]=i;
   for (int i=ans-1; i>=0; --i) swap(a[X[i]], a[Y[i]]);
   set<int> f;
   for (int i=0; i<N; ++i) if (a[i]!=s[i]) f.insert(i);
   for (int i=0; i<ans; ++i){
      P[i]=Q[i]=0;
      swap(a[X[i]], a[Y[i]]);
      swap(s[X[i]], s[Y[i]]);
      pos[s[X[i]]]=X[i];
      pos[s[Y[i]]]=Y[i];
      f.erase(X[i]); f.erase(Y[i]);
      if (a[X[i]]!=s[X[i]]) f.insert(X[i]);
      if (a[Y[i]]!=s[Y[i]]) f.insert(Y[i]);
      if (f.size()){
         int j=*f.begin(); f.erase(f.begin());
         int k=pos[a[j]];
         P[i]=j, Q[i]=k;
      }
      swap(s[P[i]], s[Q[i]]);
      pos[s[P[i]]]=P[i];
      pos[s[Q[i]]]=Q[i];
      f.erase(P[i]); f.erase(Q[i]);
      if (a[P[i]]!=s[P[i]]) f.insert(P[i]);
      if (a[Q[i]]!=s[Q[i]]) f.insert(Q[i]);
   }
   if (is_sorted(s, s+N)) return ans;
   return -1;
}

Compilation message

sorting.cpp: In member function 'int SegmentTree::dfs(int, int, int)':
sorting.cpp:56:32: warning: conversion from 'std::vector<std::pair<int*, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   56 |       int size=dsu.changes.size();
      |                ~~~~~~~~~~~~~~~~^~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 448 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 344 KB Output is correct
7 Correct 0 ms 348 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 448 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 344 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 344 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 604 KB Output is correct
12 Correct 1 ms 604 KB Output is correct

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 860 KB Output is correct
4 Correct 1 ms 860 KB Output is correct
5 Correct 2 ms 856 KB Output is correct
6 Correct 0 ms 448 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 448 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 344 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 344 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 604 KB Output is correct
12 Correct 1 ms 604 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 860 KB Output is correct
16 Correct 1 ms 860 KB Output is correct
17 Correct 2 ms 856 KB Output is correct
18 Correct 0 ms 448 KB Output is correct
19 Correct 1 ms 344 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 17 ms 4444 KB Output is correct
22 Correct 17 ms 4444 KB Output is correct
23 Correct 20 ms 4428 KB Output is correct
24 Correct 17 ms 4188 KB Output is correct
25 Correct 17 ms 4444 KB Output is correct
26 Correct 17 ms 4444 KB Output is correct
27 Correct 17 ms 4440 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 2140 KB Output is correct
2 Correct 6 ms 1880 KB Output is correct
3 Correct 13 ms 2652 KB Output is correct
4 Correct 8 ms 2652 KB Output is correct
5 Correct 10 ms 2652 KB Output is correct
6 Correct 9 ms 2652 KB Output is correct
7 Correct 10 ms 2652 KB Output is correct
8 Correct 10 ms 2652 KB Output is correct
9 Correct 11 ms 2652 KB Output is correct
10 Correct 11 ms 2820 KB Output is correct
11 Correct 10 ms 2648 KB Output is correct
12 Correct 9 ms 2580 KB Output is correct
13 Correct 10 ms 2652 KB Output is correct
14 Correct 4 ms 1372 KB Output is correct

Subtask #6
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 2140 KB Output is correct
2 Correct 6 ms 1880 KB Output is correct
3 Correct 13 ms 2652 KB Output is correct
4 Correct 8 ms 2652 KB Output is correct
5 Correct 10 ms 2652 KB Output is correct
6 Correct 9 ms 2652 KB Output is correct
7 Correct 10 ms 2652 KB Output is correct
8 Correct 10 ms 2652 KB Output is correct
9 Correct 11 ms 2652 KB Output is correct
10 Correct 11 ms 2820 KB Output is correct
11 Correct 10 ms 2648 KB Output is correct
12 Correct 9 ms 2580 KB Output is correct
13 Correct 10 ms 2652 KB Output is correct
14 Correct 4 ms 1372 KB Output is correct
15 Correct 773 ms 139500 KB Output is correct
16 Execution timed out 1027 ms 163756 KB Time limit exceeded
17 Halted 0 ms 0 KB -