Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- //#include<cstdio>
- //#include<cassert>
- //#include<iostream>
- //#include<cstring>
- //#include<algorithm>
- #include<bits/stdc++.h>
- #include<ext/pb_ds/assoc_container.hpp>
- #include<ext/pb_ds/tree_policy.hpp>
- #define MAX ((int)2e9 + 5)
- #define MAXP ((int)1e5 + 5)
- #define MAXL ((ll)1e18 + 5)
- #define MAX_X ((int)2001)
- #define MAX_Y ((int)2001)
- #define pi acos(-1)
- //#define MOD ((int)1e9 + 7)
- #define MOD ((int)998244353 + 0)
- #define BAS ((int)1e6 + 3)
- //#define BAS ((int)2e5 + 3)
- #define N ((int)2e5 + 9)
- #define eps (1e-8)
- #define fastio ios_base::sync_with_stdio(false),cin.tie(NULL)
- #define logn 17
- #define endl "\n"
- #define mpp make_pair
- #define BUCK 105
- #define LEF (idx<<1)
- #define RIG ((idx<<1)|1)
- //#define int ll
- using namespace std;
- using namespace __gnu_pbds;
- typedef long long ll;
- typedef unsigned long long ull;
- /*fast io
- ios_base::sync_with_stdio(false);
- cin.tie(NULL);
- */
- typedef tree < int, null_type, less < int >, rb_tree_tag, tree_order_statistics_node_update > o_set;
- typedef tree < pair < int, int >, null_type, less < pair < int, int > >, rb_tree_tag, tree_order_statistics_node_update > o_setp;
- /// o_set s;
- /// s.order_of_key(k) : Number of items strictly smaller than k .
- /// *(s.find_by_order(k)) : K-th element in a set (counting from zero).
- typedef long double ldd;
- mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
- int my_rand(int l, int r)
- {
- return uniform_int_distribution<int>(l,r) (rng);
- }
- pair < int , int > dfs(int n , int p) /// returns ( dis , node ) ; node is the farthest from n , dis = distance(node , n)
- {
- pair < int , int > ans = {0,n};
- for(auto nxt:vec[n]){
- if(nxt.first != p){
- pair < int , int > tmp = dfs(nxt.first , n);
- tmp.first += nxt.second;
- ans = max(ans , tmp);
- }
- }
- return ans;
- }
- int main()
- {
- pair < int , int > dia = dfs(1,0);
- int a = dia.second;
- dia = dfs(a,0);
- int b = dia.second;
- return 0;
- }
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement