Submission #1123849

#	Time	Username	Problem	Language	Result	Execution time	Memory
1123849		omar1312	Islands (IOI08_islands)	C++20	12 / 100	1196 ms	196608 KiB

islands

#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset;
#define ll long long
#define pb push_back
#define all(x) x.begin(), x.end()
const int mod = 1000000007;
const int N = 1000005;
ll a[N+2], dp[N+2], mx[N+2], d[N+2];
bool vis[N+2];
map<ll, map<ll, ll>> adj;
vector<array<ll, 2>> leafs;
vector<ll> cmp;
ll mxdep = 0;
void dfs(int n, ll cost = 0, ll dep = 0){
	vis[n] = 1;
	mxdep = max(dep, mxdep);
	d[n] = dep;
	cmp.pb(n);
	for(auto[i, j] : adj[n]){
		if(!vis[i]){
			dfs(i, j, dep + 1);
		}
	}
}
void solve(){
    ll n;
    cin>>n;
    for(int i = 1; i <= n; i++){
    	ll u, v;
    	cin>>u>>v;
    	adj[i][u] = max(adj[i][u], v);
    	adj[u][i] = max(adj[u][i], v);
    	mx[i] = max(mx[i], v);
    	mx[u] = max(mx[u], v);
    }
    auto find_cost = [&](ll n){
    	queue<array<ll, 2>> q;
    	q.push({n, 0});
    	ll mx233 = 0;
    	while(!q.empty()){
    		auto cur = q.front();
    		vis[cur[0]] = 1;
    		q.pop();
    		array<ll, 2> curmx = {0, 0};
    		mx233 = max(mx233, cur[1]);
    		for(auto [i, j] : adj[cur[0]]){
    			if(j > curmx[1] && !vis[i]){
    				curmx[0] = i;
    				curmx[1] = j;
    			}
    		}
    		if(!curmx[0])break;
    		q.push({curmx[0], cur[1] + curmx[1]});
    	}
    	return mx233;
    };
    ll ans = 0;
    for(int i = 1; i <= n; i++){
    	if(!vis[i]){
    		dfs(i);
    		for(auto j : cmp){
    			if(mxdep == d[j]){
    				leafs.pb({mx[j], j});
    			}
    			vis[j] = 0;
    		}
		    sort(all(leafs));
		    reverse(all(leafs));
    		ans += find_cost(leafs[0][1]);
    		for(auto j : cmp)vis[j] = 1;
    		leafs.clear();
    		cmp.clear();
    		mxdep = 0;
    	}
    }
    cout<<ans;
}
int main(){
cin.tie(0)->sync_with_stdio(0);
    int tt = 1;
    //cin>>tt;
    while(tt--){
        solve();
        cout<<'\n';
    }
}

• Subtask 1: 12 / 33
• Subtask 2: 0 / 3
• Subtask 3: 0 / 4
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10