oj.uz

Submission #763992

# Submission time Handle Problem Language Result Execution time Memory
763992 2023-06-23T04:50:25 Z nonono Hard route (IZhO17_road) C++14
100 / 100
 665 ms 175072 KB 
#include "bits/stdc++.h"
#define int long long
using namespace std;

void file(string name = ""){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    if(name != ""){
        freopen((name + ".inp").c_str(), "r", stdin);
        freopen((name + ".out").c_str(), "w", stdout);
    }
}

void _max(pair<int, int> &a, pair<int, int> b){
    if(a.first < b.first){
        a = b;
    } else
    if(a.first == b.first){
        a.second += b.second;
    }
}

const int mxN = 5e5 + 10;
int n;
vector<vector<int>> adj(mxN);

pair<int, int> d[mxN], f[mxN], pref[mxN], suff[mxN];
int max_hardness = 0, count_path = 1;

void dfs(int u, int p){
    d[u] = {0, 1};
    for(int v : adj[u]){
        if(v == p) continue ;
        
        dfs(v, u);
        _max(d[u], make_pair(d[v].first + 1, d[v].second));
    }
}

void _dfs(int u, int p){
    
    vector<int> b;
    vector<pair<int, int>> a;
    
    if(adj[u].size() == 1 || u > 1){
        a.push_back({f[u].first + 1, f[u].second});
    }
    
    for(int v : adj[u]){
        if(v == p) continue ;
        a.push_back({d[v].first + 1, d[v].second});
    }
    
    sort(a.begin(), a.end(), greater<pair<int, int>> ());
    
    if(a.size() >= 3 && a[0].first * (a[1].first + a[2].first) >= max_hardness){
        int curr_hardness = a[0].first * (a[1].first + a[2].first);
        int curr_path = 0;
        
        int cnt = 0;
        for(auto [x, y] : a){
            if(x == a[2].first){
                cnt += y;
            }
        }
        
        if(a[1].first == a[2].first){
            curr_path = cnt * cnt;
            for(auto [x, y] : a){
                if(x == a[2].first){
                    curr_path -= y * y;
                }
            }
            
            curr_path /= 2;
        } else 
        if(a[0].first == a[1].first){
            curr_path = (a[0].second + a[1].second) * cnt;
        } else {
            curr_path = a[1].second * cnt;
        }
        
        if(curr_hardness > max_hardness){
            max_hardness = curr_hardness;
            count_path = curr_path;
        } else {
            count_path += curr_path;
        }
    }
    
    a.clear();
    for(int v : adj[u]){
        if(v == p) continue ;
        a.push_back({d[v].first + 1, d[v].second});
        b.push_back(v);
    }
    
    pref[0] = {0, 0};
    for(int i = 1; i <= a.size(); i ++){
        pref[i] = pref[i - 1];
        _max(pref[i], a[i - 1]);
    }
    
    suff[a.size() + 1] = {0, 0};
    for(int i = a.size(); i >= 1; i --){
        suff[i] = suff[i + 1];
        _max(suff[i], a[i - 1]);
    }
    
    for(int i = 1; i <= a.size(); i ++){
        int v = b[i - 1];
        _max(f[v], pref[i - 1]);
        _max(f[v], suff[i + 1]);
        if(adj[u].size() == 1 || u > 1) _max(f[v], make_pair(f[u].first + 1, f[u].second));
    }
    
    for(int i = 1; i <= a.size(); i ++){
        int v = b[i - 1];
        _dfs(v, u);
    }
}

signed main(){
    file("");

    cin >> n;
    
    for(int i = 1; i <= n - 1; i ++){
        int u, v;
        cin >> u >> v;
        
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    
    dfs(1, 1);
    
    f[1] = {-1, 1};
    _dfs(1, 1);

    cout << max_hardness << " " << count_path << "\n";
    return 0;
}

Compilation message

road.cpp: In function 'void _dfs(long long int, long long int)':
road.cpp:61:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   61 |         for(auto [x, y] : a){
      |                  ^
road.cpp:69:22: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   69 |             for(auto [x, y] : a){
      |                      ^
road.cpp:99:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   99 |     for(int i = 1; i <= a.size(); i ++){
      |                    ~~^~~~~~~~~~~
road.cpp:110:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |     for(int i = 1; i <= a.size(); i ++){
      |                    ~~^~~~~~~~~~~
road.cpp:117:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  117 |     for(int i = 1; i <= a.size(); i ++){
      |                    ~~^~~~~~~~~~~
road.cpp: In function 'void file(std::string)':
road.cpp:9:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |         freopen((name + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
road.cpp:10:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |         freopen((name + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12020 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Correct 6 ms 12104 KB Output is correct
8 Correct 6 ms 12084 KB Output is correct
9 Correct 6 ms 12084 KB Output is correct
10 Correct 6 ms 12116 KB Output is correct
11 Correct 6 ms 12116 KB Output is correct
12 Correct 6 ms 12116 KB Output is correct
13 Correct 6 ms 12044 KB Output is correct
14 Correct 6 ms 12116 KB Output is correct
15 Correct 6 ms 12116 KB Output is correct
16 Correct 6 ms 12116 KB Output is correct
17 Correct 7 ms 12116 KB Output is correct
18 Correct 6 ms 12008 KB Output is correct
19 Correct 6 ms 12116 KB Output is correct
20 Correct 6 ms 12116 KB Output is correct
21 Correct 6 ms 12028 KB Output is correct
22 Correct 6 ms 12064 KB Output is correct
23 Correct 7 ms 12116 KB Output is correct
24 Correct 7 ms 12116 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12020 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Correct 6 ms 12104 KB Output is correct
8 Correct 6 ms 12084 KB Output is correct
9 Correct 6 ms 12084 KB Output is correct
10 Correct 6 ms 12116 KB Output is correct
11 Correct 6 ms 12116 KB Output is correct
12 Correct 6 ms 12116 KB Output is correct
13 Correct 6 ms 12044 KB Output is correct
14 Correct 6 ms 12116 KB Output is correct
15 Correct 6 ms 12116 KB Output is correct
16 Correct 6 ms 12116 KB Output is correct
17 Correct 7 ms 12116 KB Output is correct
18 Correct 6 ms 12008 KB Output is correct
19 Correct 6 ms 12116 KB Output is correct
20 Correct 6 ms 12116 KB Output is correct
21 Correct 6 ms 12028 KB Output is correct
22 Correct 6 ms 12064 KB Output is correct
23 Correct 7 ms 12116 KB Output is correct
24 Correct 7 ms 12116 KB Output is correct
25 Correct 8 ms 12736 KB Output is correct
26 Correct 9 ms 13024 KB Output is correct
27 Correct 10 ms 12992 KB Output is correct
28 Correct 8 ms 13100 KB Output is correct
29 Correct 8 ms 13012 KB Output is correct
30 Correct 8 ms 13112 KB Output is correct
31 Correct 9 ms 12984 KB Output is correct
32 Correct 8 ms 12932 KB Output is correct
33 Correct 8 ms 12884 KB Output is correct
34 Correct 9 ms 13036 KB Output is correct
35 Correct 9 ms 13060 KB Output is correct
36 Correct 9 ms 12992 KB Output is correct
37 Correct 11 ms 13140 KB Output is correct
38 Correct 9 ms 13644 KB Output is correct
39 Correct 8 ms 12860 KB Output is correct
40 Correct 10 ms 12608 KB Output is correct
41 Correct 8 ms 12552 KB Output is correct
42 Correct 8 ms 12500 KB Output is correct
43 Correct 8 ms 12372 KB Output is correct
44 Correct 8 ms 12432 KB Output is correct
45 Correct 8 ms 12472 KB Output is correct
46 Correct 7 ms 12372 KB Output is correct
47 Correct 8 ms 12628 KB Output is correct
48 Correct 8 ms 12756 KB Output is correct

Subtask #3
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12020 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Correct 6 ms 12104 KB Output is correct
8 Correct 6 ms 12084 KB Output is correct
9 Correct 6 ms 12084 KB Output is correct
10 Correct 6 ms 12116 KB Output is correct
11 Correct 6 ms 12116 KB Output is correct
12 Correct 6 ms 12116 KB Output is correct
13 Correct 6 ms 12044 KB Output is correct
14 Correct 6 ms 12116 KB Output is correct
15 Correct 6 ms 12116 KB Output is correct
16 Correct 6 ms 12116 KB Output is correct
17 Correct 7 ms 12116 KB Output is correct
18 Correct 6 ms 12008 KB Output is correct
19 Correct 6 ms 12116 KB Output is correct
20 Correct 6 ms 12116 KB Output is correct
21 Correct 6 ms 12028 KB Output is correct
22 Correct 6 ms 12064 KB Output is correct
23 Correct 7 ms 12116 KB Output is correct
24 Correct 7 ms 12116 KB Output is correct
25 Correct 8 ms 12736 KB Output is correct
26 Correct 9 ms 13024 KB Output is correct
27 Correct 10 ms 12992 KB Output is correct
28 Correct 8 ms 13100 KB Output is correct
29 Correct 8 ms 13012 KB Output is correct
30 Correct 8 ms 13112 KB Output is correct
31 Correct 9 ms 12984 KB Output is correct
32 Correct 8 ms 12932 KB Output is correct
33 Correct 8 ms 12884 KB Output is correct
34 Correct 9 ms 13036 KB Output is correct
35 Correct 9 ms 13060 KB Output is correct
36 Correct 9 ms 12992 KB Output is correct
37 Correct 11 ms 13140 KB Output is correct
38 Correct 9 ms 13644 KB Output is correct
39 Correct 8 ms 12860 KB Output is correct
40 Correct 10 ms 12608 KB Output is correct
41 Correct 8 ms 12552 KB Output is correct
42 Correct 8 ms 12500 KB Output is correct
43 Correct 8 ms 12372 KB Output is correct
44 Correct 8 ms 12432 KB Output is correct
45 Correct 8 ms 12472 KB Output is correct
46 Correct 7 ms 12372 KB Output is correct
47 Correct 8 ms 12628 KB Output is correct
48 Correct 8 ms 12756 KB Output is correct
49 Correct 507 ms 98376 KB Output is correct
50 Correct 440 ms 107136 KB Output is correct
51 Correct 469 ms 114628 KB Output is correct
52 Correct 439 ms 88012 KB Output is correct
53 Correct 425 ms 111600 KB Output is correct
54 Correct 429 ms 120796 KB Output is correct
55 Correct 400 ms 98124 KB Output is correct
56 Correct 424 ms 108020 KB Output is correct
57 Correct 427 ms 118824 KB Output is correct
58 Correct 425 ms 108932 KB Output is correct
59 Correct 470 ms 108784 KB Output is correct
60 Correct 427 ms 104268 KB Output is correct
61 Correct 650 ms 175072 KB Output is correct
62 Correct 649 ms 152368 KB Output is correct
63 Correct 665 ms 86392 KB Output is correct
64 Correct 628 ms 70608 KB Output is correct
65 Correct 589 ms 60488 KB Output is correct
66 Correct 542 ms 55276 KB Output is correct
67 Correct 543 ms 52324 KB Output is correct
68 Correct 555 ms 51276 KB Output is correct
69 Correct 584 ms 50860 KB Output is correct
70 Correct 557 ms 50600 KB Output is correct
71 Correct 543 ms 50488 KB Output is correct
72 Correct 560 ms 50796 KB Output is correct
73 Correct 527 ms 51216 KB Output is correct
74 Correct 540 ms 51928 KB Output is correct
75 Correct 513 ms 54072 KB Output is correct
76 Correct 496 ms 57664 KB Output is correct
77 Correct 437 ms 67992 KB Output is correct
78 Correct 298 ms 85908 KB Output is correct