oj.uz

Submission #824951

# Submission time Handle Problem Language Result Execution time Memory
824951 2023-08-14T12:20:11 Z Liudas Thousands Islands (IOI22_islands) C++17
55 / 100
 1000 ms 1048272 KB 
#include "islands.h"
#include <cassert>
#include <cstdio>
#include <variant>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <iostream>
using namespace std;
bool loop = false;
vector<int> path, lpath;
void dfs(int node, vector<vector<pair<int, int>>> &tree, vector<bool> &vis){
    path.push_back(node);
    if(vis[node] && !loop){
        loop = true;
        lpath = path;
        return;
    }
    vis[node] = true;
    for(auto&[l, r] : tree[node]){
        if(!r){
            r = true;
            dfs(l, tree, vis);
        }
    }
    path.pop_back();
    vis[node] = false;
}
variant<bool, vector<int>> find_journey(int N, int M, vector<int> U, vector<int> V) {
    if (N == 2){
        if(count(U.begin(), U.end(), 0) >= 2 && count(U.begin(), U.end(), 1) >= 1){
            vector<pair<int, int>> ans(M);
            for(int i = 0; i < M; i ++){
                ans[i] = {U[i], i};
            }
            sort(ans.begin(), ans.end());
            vector<int> ret = {ans[0].second, ans.back().second, ans[1].second, ans[0].second, ans.back().second, ans[1].second};
            return ret;
        }
        return false;
    }
    bool N2 = true;
    for(int i = 0; i < N; i ++){
        N2 &= ((count(U.begin(), U.end(), i) + count(V.begin(), V.end(), i)) == 2 * N - 2);
    }
    if(N2){
        vector<vector<pair<int, int>>> tree(N);
        for(int i = 0; i < M; i ++){
            tree[U[i]].push_back({V[i], i});
        }
        for(int i = 0; i < N; i ++){
            sort(tree[i].begin(), tree[i].end());
        }
        vector<int> ret = {tree[0][0].second, tree[1][0].second, tree[0][1].second, tree[2][0].second, tree[1][0].second, tree[0][0].second, tree[2][0].second, tree[0][1].second};
        return ret;
    }
    vector<vector<pair<int,int>>> tree(N);
    bool good = true;
    for(int i = 0; i < M-1; i ++){
        good = V[i] != V[i + 1];
    }
    if(good){
        for(int i = 0; i < M; i ++){
            tree[U[i]].push_back({V[i], i});
        }
        vector<int> path;
        int id = 0, par = -1;
        bool back = false;
        int NNN = 0;
        while(tree[id].size() < 3 && tree[id].size() > 0 && !back){
            NNN = max(NNN, (int)tree[id].size());
            if(tree[id].size() == 1){
                par = id;
                path.push_back(tree[id][0].second);
                id = tree[id][0].first;
            }
            else{
                if(tree[id][0].first == par){
                    path.push_back(tree[id][1].second);
                    par = id;
                    id = tree[id][1].first;
                }
                else{
                    path.push_back(tree[id][0].second);
                    par = id;
                    id = tree[id][0].first;
                }
            }
            if(id == 0){
                back = true;
            }
        }
        if(!back && tree[0].size() != 0){
            vector<int> mov, ids;
            for(auto[l, r] : tree[id]){
                if (l != par){
                    mov.push_back(l);
                    ids.push_back(r);
                }
                if(mov.size() > 1){
                    break;
                }
            }
            for(int i = 0; i < M; i ++){
                if(mov[0] == U[i] && id == V[i]){
                    ids.insert(ids.begin() + 1, i);
                    break;
                }
            }
            for(int i = 0; i < M; i ++){
                if(mov[1] == U[i] && id == V[i]){
                    ids.push_back(i);
                    break;
                }
            }
            vector<int> gap;
            if(mov[0] == mov[1]){
                gap = {ids[0], ids[1], ids[2], ids[0], ids[1], ids[2]};
            }
            else{
                gap = {ids[0], ids[1], ids[2], ids[3], ids[1], ids[0], ids[3], ids[2]};
            }
            vector<int> legit;
            for(int i : path){
                legit.push_back(i);
            }
            for(int i : gap){
                legit.push_back(i);
            }
            reverse(path.begin(), path.end());
            for(int i : path){
                legit.push_back(i);
            }
            return legit;
        }
        return false;
    }
    for(int i = 0; i < M; i ++){
        tree[U[i]].push_back({V[i], 0});
    }
    vector<bool> vis(N, 0);
    dfs(0, tree, vis);
    if(!loop){
        return false;
    }
    vector<int> arr;
    int id = find(lpath.begin(), lpath.end(), lpath.back()) - lpath.begin();
    int sz = lpath.size();
    vector<int> pre, lap1, lap2, lap1id, lap2id, preid;
    for(int i = 0; i <= id; i ++){
        pre.push_back(lpath[i]);
    }
    for(int j = id; j < sz; j ++){
        lap1.push_back(lpath[j]);
        lap2.push_back(lpath[j]);
    }
    map<pair<int, int>, set<int>> pos; 
    for(int i = 0; i < M; i ++){
        pos[{U[i], V[i]}].insert(i);
    }
    for(int i = 1; i < pre.size(); i++){
        preid.push_back(*pos[{pre[i-1], pre[i]}].begin());
        pos[{pre[i-1], pre[i]}].erase(pos[{pre[i-1], pre[i]}].begin());
    }
    for(int i = 1; i < lap1.size(); i ++){
        lap1id.push_back(*pos[{lap1[i-1], lap1[i]}].begin());
        pos[{lap1[i-1], lap1[i]}].erase(pos[{lap1[i-1], lap1[i]}].begin());
    }
    for(int i = 1; i < lap2.size(); i ++){
        lap2id.push_back(*pos[{lap2[i-1], lap2[i]}].begin());
        pos[{lap2[i-1], lap2[i]}].erase(pos[{lap2[i-1], lap2[i]}].begin());
    }
    for(int i : preid){
        arr.push_back(i);
    }
    for(int j : lap1id){
        arr.push_back(j);
    }
    for(int j : lap2id){
        arr.push_back(j);
    } 
    reverse(preid.begin(), preid.end());
    reverse(lap1id.begin(), lap1id.end());
    reverse(lap2id.begin(), lap2id.end());
    for(int j : lap1id){
        arr.push_back(j);
    }
    for(int j : lap2id){
        arr.push_back(j);
    }
    for(int i : preid){
        arr.push_back(i);
    }
    //cout << lap1id.size() << " " << lap2id.size() << " " << preid.size() <<  endl;
    return arr;
}

Compilation message

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:162:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  162 |     for(int i = 1; i < pre.size(); i++){
      |                    ~~^~~~~~~~~~~~
islands.cpp:166:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  166 |     for(int i = 1; i < lap1.size(); i ++){
      |                    ~~^~~~~~~~~~~~~
islands.cpp:170:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  170 |     for(int i = 1; i < lap2.size(); i ++){
      |                    ~~^~~~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 300 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 296 KB Output is correct
7 Correct 37 ms 5672 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 296 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 111 ms 5720 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 436 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 4 ms 340 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 3 ms 340 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 3 ms 340 KB Output is correct
11 Correct 0 ms 300 KB Output is correct
12 Correct 3 ms 340 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 1 ms 296 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 1 ms 256 KB Output is correct
17 Correct 140 ms 3768 KB Output is correct
18 Correct 109 ms 3312 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 1 ms 300 KB Output is correct
22 Correct 1 ms 304 KB Output is correct
23 Correct 106 ms 5624 KB Output is correct

Subtask #4
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 3 ms 696 KB Output is correct
3 Correct 143 ms 14616 KB Output is correct
4 Correct 348 ms 20876 KB Output is correct
5 Correct 6 ms 724 KB Output is correct
6 Correct 6 ms 724 KB Output is correct
7 Correct 0 ms 300 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 4 ms 696 KB Output is correct
11 Correct 6 ms 384 KB Output is correct
12 Correct 7 ms 772 KB Output is correct
13 Correct 8 ms 980 KB Output is correct
14 Correct 7 ms 852 KB Output is correct
15 Correct 10 ms 980 KB Output is correct
16 Correct 4 ms 596 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 7 ms 852 KB Output is correct
19 Correct 4 ms 564 KB Output is correct
20 Correct 253 ms 6840 KB Output is correct
21 Correct 353 ms 22388 KB Output is correct
22 Correct 3 ms 468 KB Output is correct
23 Correct 2 ms 340 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 468 KB Output is correct
26 Correct 4 ms 724 KB Output is correct
27 Correct 333 ms 20900 KB Output is correct
28 Correct 329 ms 21616 KB Output is correct
29 Correct 0 ms 212 KB Output is correct
30 Correct 291 ms 7704 KB Output is correct
31 Correct 1 ms 212 KB Output is correct
32 Correct 320 ms 21500 KB Output is correct
33 Correct 249 ms 15564 KB Output is correct
34 Correct 182 ms 20172 KB Output is correct
35 Correct 2 ms 468 KB Output is correct
36 Correct 284 ms 19256 KB Output is correct
37 Correct 351 ms 24004 KB Output is correct
38 Correct 2 ms 340 KB Output is correct
39 Correct 138 ms 5912 KB Output is correct
40 Correct 4 ms 596 KB Output is correct
41 Correct 294 ms 7640 KB Output is correct
42 Correct 338 ms 21992 KB Output is correct
43 Correct 1 ms 212 KB Output is correct
44 Correct 6 ms 360 KB Output is correct
45 Correct 4 ms 724 KB Output is correct
46 Correct 139 ms 16264 KB Output is correct

Subtask #5
0.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 300 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 296 KB Output is correct
7 Correct 37 ms 5672 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 1 ms 296 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 111 ms 5720 KB Output is correct
14 Correct 6 ms 436 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 4 ms 340 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 3 ms 340 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 1 ms 212 KB Output is correct
23 Correct 3 ms 340 KB Output is correct
24 Correct 0 ms 300 KB Output is correct
25 Correct 3 ms 340 KB Output is correct
26 Correct 0 ms 212 KB Output is correct
27 Correct 1 ms 296 KB Output is correct
28 Correct 0 ms 212 KB Output is correct
29 Correct 1 ms 256 KB Output is correct
30 Correct 140 ms 3768 KB Output is correct
31 Correct 109 ms 3312 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 0 ms 212 KB Output is correct
34 Correct 1 ms 300 KB Output is correct
35 Correct 1 ms 304 KB Output is correct
36 Correct 106 ms 5624 KB Output is correct
37 Execution timed out 1119 ms 1048272 KB Time limit exceeded
38 Halted 0 ms 0 KB -