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Submission #1087416

# Submission time Handle Problem Language Result Execution time Memory
1087416 2024-09-12T16:07:23 Z watse Love Polygon (BOI18_polygon) C++14
75 / 100
 410 ms 59796 KB 
#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair <ll,ll> pll;
typedef pair <int,int> pii;
typedef pair <int,pii> piii;

#define forr(_a,_b,_c) for(int _a = (_b); _a <= int (_c); ++_a)
#define ford(_a,_b,_c) for(int _a = (_b) + 1; _a --> int (_c);)
#define forf(_a,_b,_c) for(int _a = (_b); _a < int (_c); ++_a)
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define all(x) begin(x),end(x)
#define mask(i) (1LL << (i))
#define bit(x, i) (((x) >> (i)) & 1)
#define bp __builtin_popcountll
#define file "test"

template<class X, class Y>
    bool minz(X &x, const Y &y) {
        if (x > y) {
            x = y;
            return true;
        } return false;
    }
template<class X, class Y>
    bool maxz(X &x, const Y &y) {
        if (x < y) {
            x = y;
            return true;
        } return false;
    }

const int N = 5e5 + 5;
const ll oo = (ll) 1e16;
const ll mod = 1e9 + 7; // 998244353;

int vis[N], edge[N], dp[N][4], ban[N], n, rem[N];
vector <int> a[N], ra[N];
vector <pair<pii, pii>> s;
string u, v;
map <string, int> id;

void dfs (int u, int p){    
    vis[u] = 1;

    for (int i : a[u]){
        int v = edge[i] ^ u;
        if (rem[v]) continue;
        if (v != p && vis[v] == 0){
            dfs(v, u);
        } else if (vis[v] == 1){
            pair<pii, pii> ww;
            ww.st = mp(u, i);
            for (int j : a[v]){
                int w = edge[j] ^ u;
                if (vis[w] == 1){
                    ww.nd = mp(v, j);
                    break;
                }
            }
            s.pb(ww);
        }
    }

    vis[u] = 2;
}

void go (int u){
    dp[u][0] = dp[u][1] = 0;

    for (int i : ra[u]){
        int v = edge[i] ^ u;
        if (ban[i] || rem[v]) continue;
        go(v);
        dp[u][1] = max (dp[u][1] + dp[v][1], dp[u][0] + dp[v][0] + 1);
        dp[u][0] += dp[v][1];
    }

    dp[u][1] = max (dp[u][0], dp[u][1]);
}

int cnt;
map <pii, int> c2;

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef hqm
        freopen(file".inp", "r", stdin); freopen(file".out", "w", stdout);
    #endif

    cin >> n;

    if (n & 1){
        cout << "-1\n";
        return 0;
    }

    int res = 0;

    forr (i, 1, n){
        cin >> u >> v;
     
        if (!id.count(u))
            id[u] = ++cnt;
    
        if (!id.count(v))
            id[v] = ++cnt;
    
        a[id[u]].pb(i);
        ra[id[v]].pb(i);
        edge[i] = id[u] ^ id[v];
        c2[mp(id[u], id[v])] = 1;
        if (c2.count(mp(id[v], id[u])) && u != v){
            rem[id[u]] = rem[id[v]] = 1;
            //cout << u << " " << v << endl;
            res += 2;
        }
    }

    for (pair <string, int> w : id){
  //      cout << w.st << " " << w.nd << endl;
    }

    forr (i, 1, n)
    if (rem[i]){
        for (int j : ra[i])
            edge[j] = 0;
    }

    forr (i, 1, n)
    if (!vis[i] && !rem[i])
        dfs(i, -1);

    for (pair<pii, pii> e : s){
        pii u = e.st, v = e.nd;
        //cout << u.st << " " << (edge[u.nd] ^ u.st) << " " << v.st << " " << (edge[v.nd] ^ v.st) << endl;
        ban[u.nd] = 1;
        go(u.st);
        int ans = dp[u.st][1];
        ban[u.nd] = 0;
        ban[v.nd] = 1;
        go(v.st);
        maxz(ans, dp[v.st][1]);
        ban[v.nd] = 0;
        res += ans;
    }

    cout << n - res << "\n";

    return 0;
}
/*



*/

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 23900 KB Output is correct
2 Correct 10 ms 23900 KB Output is correct
3 Correct 11 ms 23932 KB Output is correct
4 Correct 10 ms 23900 KB Output is correct
5 Correct 10 ms 23928 KB Output is correct
6 Correct 10 ms 23928 KB Output is correct
7 Correct 10 ms 23900 KB Output is correct
8 Correct 15 ms 23900 KB Output is correct
9 Correct 11 ms 23900 KB Output is correct
10 Correct 12 ms 23824 KB Output is correct
11 Correct 10 ms 23896 KB Output is correct
12 Correct 10 ms 23856 KB Output is correct
13 Correct 10 ms 23844 KB Output is correct
14 Correct 11 ms 23976 KB Output is correct
15 Correct 12 ms 23896 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23900 KB Output is correct
2 Correct 10 ms 23896 KB Output is correct
3 Correct 11 ms 23900 KB Output is correct
4 Correct 410 ms 58528 KB Output is correct
5 Correct 357 ms 49876 KB Output is correct
6 Correct 398 ms 59796 KB Output is correct
7 Correct 11 ms 23900 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 386 ms 48308 KB Output is correct
2 Correct 387 ms 50000 KB Output is correct
3 Correct 285 ms 50892 KB Output is correct
4 Correct 11 ms 23900 KB Output is correct
5 Correct 374 ms 56104 KB Output is correct
6 Correct 356 ms 47200 KB Output is correct
7 Correct 355 ms 47624 KB Output is correct
8 Correct 315 ms 48844 KB Output is correct
9 Correct 323 ms 46876 KB Output is correct
10 Correct 221 ms 46088 KB Output is correct
11 Correct 10 ms 23896 KB Output is correct
12 Correct 10 ms 23900 KB Output is correct
13 Correct 11 ms 23900 KB Output is correct
14 Correct 10 ms 23940 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 23900 KB Output is correct
2 Correct 10 ms 23900 KB Output is correct
3 Correct 11 ms 23932 KB Output is correct
4 Correct 10 ms 23900 KB Output is correct
5 Correct 10 ms 23928 KB Output is correct
6 Correct 10 ms 23928 KB Output is correct
7 Correct 10 ms 23900 KB Output is correct
8 Correct 15 ms 23900 KB Output is correct
9 Correct 11 ms 23900 KB Output is correct
10 Correct 12 ms 23824 KB Output is correct
11 Correct 10 ms 23896 KB Output is correct
12 Correct 10 ms 23856 KB Output is correct
13 Correct 10 ms 23844 KB Output is correct
14 Correct 11 ms 23976 KB Output is correct
15 Correct 12 ms 23896 KB Output is correct
16 Correct 12 ms 23900 KB Output is correct
17 Correct 10 ms 23896 KB Output is correct
18 Correct 11 ms 23900 KB Output is correct
19 Correct 410 ms 58528 KB Output is correct
20 Correct 357 ms 49876 KB Output is correct
21 Correct 398 ms 59796 KB Output is correct
22 Correct 11 ms 23900 KB Output is correct
23 Correct 386 ms 48308 KB Output is correct
24 Correct 387 ms 50000 KB Output is correct
25 Correct 285 ms 50892 KB Output is correct
26 Correct 11 ms 23900 KB Output is correct
27 Correct 374 ms 56104 KB Output is correct
28 Correct 356 ms 47200 KB Output is correct
29 Correct 355 ms 47624 KB Output is correct
30 Correct 315 ms 48844 KB Output is correct
31 Correct 323 ms 46876 KB Output is correct
32 Correct 221 ms 46088 KB Output is correct
33 Correct 10 ms 23896 KB Output is correct
34 Correct 10 ms 23900 KB Output is correct
35 Correct 11 ms 23900 KB Output is correct
36 Correct 10 ms 23940 KB Output is correct
37 Correct 388 ms 48448 KB Output is correct
38 Incorrect 386 ms 49236 KB Output isn't correct
39 Halted 0 ms 0 KB -