제출 #466339

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
466339		MohamedAliSaidane	Islands (IOI08_islands)	C++14	24 / 100	541 ms	55124 KiB

islands

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;

typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ld,ld> pld;

typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pii> vpi;

#define pb push_back
#define popb pop_back
#define all(v) (v).begin(),(v).end()
#define ff first
#define ss second

const int MOD = 1e9 + 7;
const ll INF = 1e18;
vi p, rnk, setsz;
int n;

int findset(int i){ return p[i] == i? i: findset(p[i]);}

void unite(int i, int j)
{
    if(findset(i) == findset(j))
        return;
    int x= findset(i);
    int y = findset(j);
    if(rnk[x] > rnk[y])
        swap(x,y);
    p[x] = y;
    if(rnk[x] == rnk[y])
        rnk[y] ++;
    setsz[y] += setsz[x];
    return;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    vector<pair<ll,pll>> edges;
    cin >> n;
    int deg[n+1];
    memset(deg,0,sizeof(deg));
    p.assign(n+1,0);
    rnk.assign(n+1,0);
    setsz.assign(n+1,1);
    for(ll i = 1; i <=n; i ++)
    {
        p[i-1] = i-1;
        ll u, dist;
        cin >> u >> dist;
        edges.pb({dist,{i,u}});
    }
    sort(all(edges));
    reverse(all(edges));
    ll ans = 0;
    for(int j = 0; j < n; j ++)
    {
        ll d = edges[j].ff;
        ll u = edges[j].ss.ff - 1;
        ll v = edges[j].ss.ss - 1;
        if(findset(u) == findset(v))
            continue;
        else if(deg[u] < 2 && deg[v] < 2)
        {
            deg[u] ++;
            deg[v] ++;
            ans += d;
            unite(u,v);
        }
    }
    cout << ans << '\n';
}
/*
Sample test case:
7
3 8
7 2
4 2
1 4
1 9
3 4
2 3
*/

• Subtask 1: 24 / 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