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Submission #1087417

# Submission time Handle Problem Language Result Execution time Memory
1087417 2024-09-12T16:10:48 Z watse Love Polygon (BOI18_polygon) C++14
100 / 100
 424 ms 59740 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;
                    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;
        }
    }


    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;
}
/*



*/

Compilation message

polygon.cpp: In function 'void dfs(int, int)':
polygon.cpp:59:21: warning: unused variable 'w' [-Wunused-variable]
   59 |                 int w = edge[j] ^ u;
      |                     ^

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23900 KB Output is correct
2 Correct 10 ms 23948 KB Output is correct
3 Correct 10 ms 23984 KB Output is correct
4 Correct 11 ms 23896 KB Output is correct
5 Correct 13 ms 23900 KB Output is correct
6 Correct 11 ms 23900 KB Output is correct
7 Correct 11 ms 23956 KB Output is correct
8 Correct 10 ms 23896 KB Output is correct
9 Correct 11 ms 23900 KB Output is correct
10 Correct 10 ms 23896 KB Output is correct
11 Correct 10 ms 23900 KB Output is correct
12 Correct 10 ms 23900 KB Output is correct
13 Correct 10 ms 23900 KB Output is correct
14 Correct 10 ms 23900 KB Output is correct
15 Correct 10 ms 23880 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 23896 KB Output is correct
2 Correct 10 ms 23900 KB Output is correct
3 Correct 10 ms 23900 KB Output is correct
4 Correct 377 ms 58212 KB Output is correct
5 Correct 343 ms 49872 KB Output is correct
6 Correct 383 ms 59540 KB Output is correct
7 Correct 10 ms 23900 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 371 ms 48460 KB Output is correct
2 Correct 367 ms 50156 KB Output is correct
3 Correct 270 ms 50888 KB Output is correct
4 Correct 10 ms 23896 KB Output is correct
5 Correct 424 ms 55840 KB Output is correct
6 Correct 332 ms 47184 KB Output is correct
7 Correct 369 ms 47696 KB Output is correct
8 Correct 304 ms 48792 KB Output is correct
9 Correct 300 ms 46672 KB Output is correct
10 Correct 212 ms 46024 KB Output is correct
11 Correct 10 ms 23896 KB Output is correct
12 Correct 10 ms 23952 KB Output is correct
13 Correct 10 ms 23900 KB Output is correct
14 Correct 10 ms 23900 KB Output is correct

Subtask #4
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23900 KB Output is correct
2 Correct 10 ms 23948 KB Output is correct
3 Correct 10 ms 23984 KB Output is correct
4 Correct 11 ms 23896 KB Output is correct
5 Correct 13 ms 23900 KB Output is correct
6 Correct 11 ms 23900 KB Output is correct
7 Correct 11 ms 23956 KB Output is correct
8 Correct 10 ms 23896 KB Output is correct
9 Correct 11 ms 23900 KB Output is correct
10 Correct 10 ms 23896 KB Output is correct
11 Correct 10 ms 23900 KB Output is correct
12 Correct 10 ms 23900 KB Output is correct
13 Correct 10 ms 23900 KB Output is correct
14 Correct 10 ms 23900 KB Output is correct
15 Correct 10 ms 23880 KB Output is correct
16 Correct 9 ms 23896 KB Output is correct
17 Correct 10 ms 23900 KB Output is correct
18 Correct 10 ms 23900 KB Output is correct
19 Correct 377 ms 58212 KB Output is correct
20 Correct 343 ms 49872 KB Output is correct
21 Correct 383 ms 59540 KB Output is correct
22 Correct 10 ms 23900 KB Output is correct
23 Correct 371 ms 48460 KB Output is correct
24 Correct 367 ms 50156 KB Output is correct
25 Correct 270 ms 50888 KB Output is correct
26 Correct 10 ms 23896 KB Output is correct
27 Correct 424 ms 55840 KB Output is correct
28 Correct 332 ms 47184 KB Output is correct
29 Correct 369 ms 47696 KB Output is correct
30 Correct 304 ms 48792 KB Output is correct
31 Correct 300 ms 46672 KB Output is correct
32 Correct 212 ms 46024 KB Output is correct
33 Correct 10 ms 23896 KB Output is correct
34 Correct 10 ms 23952 KB Output is correct
35 Correct 10 ms 23900 KB Output is correct
36 Correct 10 ms 23900 KB Output is correct
37 Correct 375 ms 48468 KB Output is correct
38 Correct 335 ms 49100 KB Output is correct
39 Correct 377 ms 48388 KB Output is correct
40 Correct 342 ms 47100 KB Output is correct
41 Correct 340 ms 47188 KB Output is correct
42 Correct 336 ms 47696 KB Output is correct
43 Correct 387 ms 47704 KB Output is correct
44 Correct 367 ms 47560 KB Output is correct
45 Correct 356 ms 47600 KB Output is correct
46 Correct 368 ms 47696 KB Output is correct
47 Correct 326 ms 46972 KB Output is correct
48 Correct 366 ms 48464 KB Output is correct
49 Correct 385 ms 50000 KB Output is correct
50 Correct 273 ms 50808 KB Output is correct
51 Correct 10 ms 23896 KB Output is correct
52 Correct 379 ms 55880 KB Output is correct
53 Correct 339 ms 47304 KB Output is correct
54 Correct 357 ms 47696 KB Output is correct
55 Correct 299 ms 48840 KB Output is correct
56 Correct 302 ms 46928 KB Output is correct
57 Correct 208 ms 45872 KB Output is correct
58 Correct 10 ms 23896 KB Output is correct
59 Correct 10 ms 23896 KB Output is correct
60 Correct 10 ms 23900 KB Output is correct
61 Correct 11 ms 23864 KB Output is correct
62 Correct 12 ms 23896 KB Output is correct
63 Correct 10 ms 23900 KB Output is correct
64 Correct 10 ms 23820 KB Output is correct
65 Correct 398 ms 58344 KB Output is correct
66 Correct 377 ms 49940 KB Output is correct
67 Correct 410 ms 59740 KB Output is correct
68 Correct 10 ms 23896 KB Output is correct
69 Correct 10 ms 23900 KB Output is correct
70 Correct 10 ms 23900 KB Output is correct
71 Correct 13 ms 23936 KB Output is correct
72 Correct 10 ms 23900 KB Output is correct
73 Correct 10 ms 23776 KB Output is correct
74 Correct 10 ms 23900 KB Output is correct
75 Correct 12 ms 23896 KB Output is correct
76 Correct 9 ms 23932 KB Output is correct
77 Correct 10 ms 23824 KB Output is correct
78 Correct 10 ms 23900 KB Output is correct
79 Correct 10 ms 23736 KB Output is correct
80 Correct 11 ms 23900 KB Output is correct
81 Correct 11 ms 23900 KB Output is correct
82 Correct 11 ms 23812 KB Output is correct
83 Correct 14 ms 23896 KB Output is correct