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Record Detail

Wrong Answer


  
# Status Time Cost Memory Cost
#1 Accepted 1ms 336.0 KiB
#2 Wrong Answer 43ms 7.094 MiB
#3 Accepted 47ms 7.004 MiB
#4 Accepted 45ms 7.098 MiB
#5 Accepted 45ms 7.055 MiB
#6 Accepted 46ms 7.156 MiB
#7 Wrong Answer 44ms 7.062 MiB

Code

//████████╗██╗███╗░░██╗  ██╗░░░░░███████╗
//╚══██╔══╝██║████╗░██║  ██║░░░░░██╔════╝
//░░░██║░░░██║██╔██╗██║  ██║░░░░░█████╗░░
//░░░██║░░░██║██║╚████║  ██║░░░░░██╔══╝░░
//░░░██║░░░██║██║░╚███║  ███████╗███████╗
//░░░╚═╝░░░╚═╝╚═╝░░╚══╝  ╚══════╝╚══════╝
//   __________________
//  | ________________ |
//  ||          ____  ||
//  ||   /\    |      ||
//  ||  /__\   |      ||
//  || /    \  |____  ||
//  ||________________||
//  |__________________|
//  \###################\
//   \###################\
//    \        ____       \
//     \_______\___\_______\
// An AC a day keeps the doctor away.

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define vt vector
#define all(x) begin(x), end(x)
#define allr(x) rbegin(x), rend(x)
#define ub upper_bound
#define lb lower_bound
#define db double
#define ld long db
#define ll int64_t
#define vll vt<ll>  
#define vvll vt<vll>
#define pll pair<ll, ll>    
#define vpll vt<pll>
#define vc vt<char> 
#define vvc vt<vc>
#define vi vt<int>
#define vvi vt<vi>
#define vvvi vt<vvi>
#define pii pair<int, int>
#define vpii vt<pii>
#define vs vt<string>
#define vvs vt<vs>
#define vb vt<bool>
#define vvb vt<vb>
#define vvpii vt<vpii>
#define vd vt<db>
#define ar(x) array<int, x>
#define var(x) vt<ar(x)>
#define pq priority_queue
#define mset(m, v) memset(m, v, sizeof(m))
#define pb push_back
#define ff first
#define ss second
#define sv string_view
#define MP make_pair
#define MT make_tuple
#define rsz resize
#define sum(x) accumulate(all(x), 0LL)
#define srt(x) sort(all(x))
#define srtR(x) sort(allr(x))
#define srtU(x) sort(all(x)), (x).erase(unique(all(x)), (x).end())
#define SORTED(x) is_sorted(all(x))
#define rev(x) reverse(all(x))
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) (a * b) / gcd(a, b)
#define MAX(a) *max_element(all(a)) 
#define MIN(a) *min_element(all(a))

//SGT DEFINE
#define lc i * 2 + 1
#define rc i * 2 + 2
#define lp lc, left, middle
#define rp rc, middle + 1, right
#define entireTree 0, 0, n - 1
#define midPoint left + (right - left) / 2
#define pushDown push(i, left, right)
#define iterator int i, int left, int right

#define IOS ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

struct custom {
    static const uint64_t C = 0x9e3779b97f4a7c15; const uint32_t RANDOM = std::chrono::steady_clock::now().time_since_epoch().count();
    size_t operator()(uint64_t x) const { return __builtin_bswap64((x ^ RANDOM) * C); }
    size_t operator()(const std::string& s) const { size_t hash = std::hash<std::string>{}(s); return hash ^ RANDOM; } };
template <class K, class V> using umap = std::unordered_map<K, V, custom>; template <class K> using uset = std::unordered_set<K, custom>;
    
template<typename T1, typename T2>
std::ostream& operator<<(std::ostream& o, const std::pair<T1, T2>& p) { return o << "{" << p.ff << " , " << p.ss << "}"; }
auto operator<<(auto &o, const auto &x) -> decltype(end(x), o) {
    o << "{"; int i = 0; for (const auto &e : x) { if (i++) o << " , "; o << e; } return o << "}";
}
    
template <typename T1, typename T2>  istream &operator>>(istream& in, pair<T1, T2>& input) {    return in >> input.ff >> input.ss; }
    
template <typename T> istream &operator>>(istream &in, vector<T> &v) { for (auto &el : v) in >> el; return in; }
    
template<typename K, typename V>
auto operator<<(std::ostream &o, const std::map<K, V> &m) -> std::ostream& {
    o << "{"; int i = 0;
    for (const auto &[key, value] : m) { if (i++) o << " , "; o << key << " : " << value; }
    return o << "}";
}
    
template<typename T> vt<T> uniqued(vt<T> arr) {  srtU(arr); return arr; }

#ifdef LOCAL
#define debug(x...) debug_out(#x, x)
void debug_out(const char* names) { std::cerr << std::endl; }
template <typename T, typename... Args>
void debug_out(const char* names, T value, Args... args) {
    const char* comma = strchr(names, ',');
    std::cerr << "[" << (comma ? std::string(names, comma) : names) << " = " << value << "]";
    if (sizeof...(args)) { std::cerr << ", "; debug_out(comma + 1, args...); }   
    else { std::cerr << std::endl; }
}
#define startClock clock_t tStart = clock();
#define endClock std::cout << std::fixed << std::setprecision(10) << "\nTime Taken: " << (double)(clock() - tStart) / CLOCKS_PER_SEC << " seconds" << std::endl;
#else
#define debug(...)
#define startClock
#define endClock

#endif
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

#define eps 1e-9
#define M_PI 3.14159265358979323846
const static ll INF = 1LL << 60;
const static int inf = 1e9 + 33;
const static int MK = 20;
const static int MX = 2e6 + 5;
const static int MOD = 1e9 + 7;
int pct(int x) { return __builtin_popcountll(x); }
const vvi dirs = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}, {1, 1}, {-1, -1}, {1, -1}, {-1, 1}}; // UP, DOWN, LEFT, RIGHT
int modExpo(ll base, ll exp, ll mod) { ll res = 1; base %= mod; while(exp) { if(exp & 1) res = (res * base) % mod; base = (base * base) % mod; exp >>= 1; } return res; }

void solve() {
int N;
        cin >> N; // Number of nodes in the tree
        
        // Initialize adjacency list for the tree
        vvi graph(N + 1, vi());
        
        // Degree array to keep track of connections each node has
        vi degree(N + 1, 0);
        
        // Read N-1 edges and build the tree
        for(int i = 0; i < N - 1; i++){
            int u, v;
            cin >> u >> v;
            graph[u].push_back(v);
            graph[v].push_back(u);
            degree[u]++;
            degree[v]++;
        }
        
        // Queue to perform BFS (Layered Leaf Removal)
        queue<pii> q;
        
        // Enqueue all initial leaves with day count 0
        for(int i = 1; i <= N; i++){
            if(degree[i] == 1){
                q.push({0, i});
            }
        }
        
        // Variables to store the final answer
        int min_days = 0;      // Minimum number of days required
        int optimal_node = 0;  // Optimal node to inject the vaccine
        
        // Perform BFS to peel off leaves layer by layer
        while(!q.empty()){
            int size = q.size(); // Number of nodes in the current layer
            
            // Temporary vector to store nodes in the current layer
            vector<int> current_layer_nodes;
            int current_day = 0;
            
            // Process all nodes in the current layer
            for(int i = 0; i < size; i++){
                pii current = q.front(); q.pop();
                current_day = current.first;
                int node = current.second;
                current_layer_nodes.push_back(node);
                
                // Iterate through all neighbors of the current node
                for(auto &neighbor : graph[node]){
                    degree[neighbor]--;
                    if(degree[neighbor] == 1){
                        q.push({current_day + 1, neighbor});
                    }
                }
            }
            
            // Update min_days and optimal_node based on the current layer
            if(!current_layer_nodes.empty()){
                min_days = current_day;
                // Select the node with the largest number in the current layer
                optimal_node = *max_element(current_layer_nodes.begin(), current_layer_nodes.end());
            }
        }
        
        // Output the result for the current test case
        cout << min_days << ' ' << optimal_node << '\n';
}

signed main() {
    IOS;
    startClock
    //generatePrime();

    int t = 1;
    //cin >> t;
    for(int i = 1; i <= t; i++) {   
        //cout << "Case #" << i << ": ";  
        solve();
    }

    //endClock
    return 0;
}

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Information

Submit By
Type
Submission
Problem
P1069 Vaccination
Language
C++17 (G++ 13.2.0)
Submit At
2024-10-05 04:11:43
Judged At
2024-11-11 02:40:48
Judged By
Score
25
Total Time
47ms
Peak Memory
7.156 MiB