Submission #1105855

# Submission time Handle Problem Language Result Execution time Memory
1105855 2024-10-28T04:19:47 Z koukirocks Love Polygon (BOI18_polygon) C++17
29 / 100
122 ms 18320 KB
#include <bits/stdc++.h>
#define speed ios_base::sync_with_stdio(0); cin.tie(0)
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx,avx2")
//#pragma GCC target("popcnt")
 
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
 
const ll MAX=2e5+10,P=1e9+7;
const ll INF=0x3f3f3f3f,oo=0x3f3f3f3f3f3f3f3f;
const ldb eps=1e-6;
const ldb PI=acos(-1.0);
const int dir[4][2]={{0,1},{0,-1},{1,0},{-1,0}};
template<typename T>
using vvector = vector<vector<T>>;

int main() {
    speed;
    int n;
    vector<pair<string,string>> e;
    vector<string> d;
    cin>>n;
    for (int i=0;i<n;i++) {
        string a,b;
        cin>>a>>b;
        e.emplace_back(a,b);
        d.push_back(a);
        d.push_back(b);
    }
    if (n&1) {
        cout<<"-1\n";
        return 0;
    }
    sort(all(d));
    d.resize(unique(all(d))-d.begin());
    n=d.size();
    vector<int> G(n+1);
    vector<int> ind(n+1),vis(n+1);
    int ans=0;
    for (int i=0;i<n;i++) {
        int a=lower_bound(all(d),e[i].F)-d.begin()+1,b=lower_bound(all(d),e[i].S)-d.begin()+1;
        // if (a==b) G[a]=0;
        // else {
            G[a]=b;
            ind[b]++;
        // }
    }
    queue<int> q;
    for (int i=1;i<=n;i++) {
        if (ind[i]==0) q.push(i);
    }
    while (!q.empty()) {
        int v=q.front();
        q.pop();
        ans++;
        if (!vis[G[v]]) {
            // cout<<v<<" "<<G[v]<<" v gv\n";
            vis[G[v]]=true;
            ind[G[G[v]]]--;
            if (ind[G[G[v]]]==0 and !vis[G[G[v]]]) q.push(G[G[v]]);
        }
        // cout<<v<<" v\n";
        vis[v]=true;
    }
    for (int i=1;i<=n;i++) {
        if (vis[i]) continue;
        int now=i;
        int sz=0;
        while (!vis[now]) {
            vis[now]=true;
            sz++;
            now=G[now];
        }
        if (sz==1) ans++;
        else if (sz!=2) {
            ans+=sz/2+sz&1;
        }
    }
    cout<<ans<<"\n";
    return 0;
}

Compilation message

polygon.cpp: In function 'int main()':
polygon.cpp:85:22: warning: suggest parentheses around '+' in operand of '&' [-Wparentheses]
   85 |             ans+=sz/2+sz&1;
      |                  ~~~~^~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct
6 Correct 0 ms 336 KB Output is correct
7 Incorrect 1 ms 336 KB Output isn't correct
8 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 508 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Incorrect 1 ms 336 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 100 ms 18056 KB Output is correct
2 Correct 110 ms 17856 KB Output is correct
3 Correct 103 ms 17852 KB Output is correct
4 Correct 18 ms 17232 KB Output is correct
5 Correct 107 ms 17852 KB Output is correct
6 Correct 100 ms 18064 KB Output is correct
7 Correct 122 ms 18108 KB Output is correct
8 Correct 107 ms 18116 KB Output is correct
9 Correct 106 ms 18320 KB Output is correct
10 Correct 84 ms 18320 KB Output is correct
11 Correct 1 ms 508 KB Output is correct
12 Correct 1 ms 336 KB Output is correct
13 Correct 1 ms 336 KB Output is correct
14 Correct 1 ms 336 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct
6 Correct 0 ms 336 KB Output is correct
7 Incorrect 1 ms 336 KB Output isn't correct
8 Halted 0 ms 0 KB -