oj.uz

Submission #643706

# Submission time Handle Problem Language Result Execution time Memory
643706 2022-09-22T19:25:48 Z ParsaS Love Polygon (BOI18_polygon) C++14
100 / 100
 471 ms 40204 KB 
// In the name of God
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
typedef long long ll;
const int N = 1e5 + 5, MOD = 1e9 + 7;
int n;
vector<int> adj[N];
map<string, int> M;
bool vis[N];
int cnt, par[N], h[N], C[3][N];
vector<int> V;

void dfs(int v) {
    vis[v] = true;
    cnt++;
    V.pb(v);
    for (auto u : adj[v]) {
        if (!vis[u]) {
            par[u] = v;
            h[u] = h[v] + 1;
            dfs(u);
        }
    }
}

void dfs2(int v) {
    vis[v] = true;
    C[2][v] = 1;
    int mx = 0;
    for (auto u : adj[v]) {
        if (vis[u])
            continue;
        dfs2(u);
        C[2][v] += C[1][u];
        C[0][v] += C[1][u];
        mx = max(mx, C[2][u] - C[1][u]);
    }
    C[1][v] = C[0][v] + mx;
    C[1][v] = max(C[1][v], C[0][v]);
}
int dp[N][3];
/*int DP(vector<int> vec) {
    assert(vec.empty());
    if (vec.empty()) {
        return 0;
    }
    for (int i = 0; i < vec.size(); i++) {
        int v = vec[i];
        dp[i] = (i ? dp[i - 1] : 0) + C[1][v];
        dp[i] = max(dp[i], (i - 1 ? dp[i - 2] : 0) + C[0][v] + (i ? C[1][vec[i - 1]] : 0));
    }
    return dp[(int)vec.size() - 1];
}*/

int SOLVE(int x) {
    V.clear();
    cnt = 0;
    dfs(x);
    int up = x, dn = x;
    bool ok = true;
    for (auto v : V) {
        int c = 0;
        for (auto u : adj[v]) {
            c += u == par[v];
            if (h[u] < h[v] - 1) {
                up = u;
                dn = v;
            }
            if (u == v) {
                ok = false;
                dn = up = v;
            }
        }
        if (c > 1) {
            dn = v;
            up = par[v];
        }
    }
    int xx = dn;
    vector<int> cle;
    while (dn != up) {
        cle.pb(dn);
        dn = par[dn];
    }
    cle.pb(up);
    for (auto v : V)
        vis[v] = false;
    for (auto v : cle)
        vis[v] = true;
    for (auto v : cle) {
        dfs2(v);
    }
    reverse(cle.begin(), cle.end());
    if (cle.size() == 1) {
        return max(C[0][up], C[1][up]);
    }
    if (cle.size() == 2) {
        return max(C[2][up] + C[2][xx], max(C[0][up], C[1][up]) + max(C[0][xx], C[1][xx]));
    }
    int v = cle.front();
    // 0:
    dp[0][0] = 0, dp[0][1] = 0; 

    for (int i = 1; i < cle.size(); i++) {
        int u = cle[i];
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]) + C[1][u];
        dp[i][1] = C[2][u] + (i > 1 ? C[0][cle[i - 1]] : 0) + (i > 2 ? max(dp[i - 2][1], dp[i - 2][0]) : 0);
    }
    int ans = max(dp[(int)cle.size() - 1][0], dp[(int)cle.size() - 1][1]) + C[0][v];
    // 1:
    dp[1][0] = max(C[0][cle[1]], C[1][cle[1]]);
    dp[1][1] = 0;
    for (int i = 2; i < cle.size(); i++) {
        int u = cle[i];
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]) + C[1][u];
        dp[i][1] = C[2][u] + (i > 1 ? C[0][cle[i - 1]] : 0) + (i > 2 ? max(dp[i - 2][1], dp[i - 2][0]) : 0);
    }
    ans = max(ans, max(dp[(int)cle.size() - 1][1], dp[(int)cle.size() - 1][0]) + C[1][v]);
    // 2:
    dp[1][0] = C[1][cle[1]];
    dp[1][1] = 0;
    for (int i = 2; i < cle.size(); i++) {
        int u = cle[i];
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]) + C[1][u];
        dp[i][1] = C[2][u] + (i > 1 ? C[0][cle[i - 1]] : 0) + (i > 2 ? max(dp[i - 2][1], dp[i - 2][0]) : 0);
    }
    ans = max(ans, C[0][cle.back()] + C[2][v] + max(dp[(int)cle.size() - 2][1], dp[(int)cle.size() - 2][0]));
    return ans;
}

void solve() {
    cin >> n;
    set<string> S;
    vector<pair<string, string> > tmp;
    for (int i = 0; i < n; i++) {
        string a, b; cin >> a >> b;
        tmp.pb(make_pair(a, b));
        S.insert(a), S.insert(b);
    }
    int inx = 0;
    for (auto s : S) {
        M[s] = ++inx;
    }
    for (auto [a, b] : tmp) {
        adj[M[a]].pb(M[b]);
        adj[M[b]].pb(M[a]);
    }

    if (n % 2) {
        cout << -1 << endl;
        return;
    }
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        if (!vis[i]) {
            ans += SOLVE(i);
        }
    }
    cout << n - ans << endl;
}

int32_t main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    solve();

    return 0;
}

Compilation message

polygon.cpp: In function 'int SOLVE(int)':
polygon.cpp:107:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |     for (int i = 1; i < cle.size(); i++) {
      |                     ~~^~~~~~~~~~~~
polygon.cpp:116:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  116 |     for (int i = 2; i < cle.size(); i++) {
      |                     ~~^~~~~~~~~~~~
polygon.cpp:125:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  125 |     for (int i = 2; i < cle.size(); i++) {
      |                     ~~^~~~~~~~~~~~
polygon.cpp:63:10: warning: variable 'ok' set but not used [-Wunused-but-set-variable]
   63 |     bool ok = true;
      |          ^~
polygon.cpp: In function 'void solve()':
polygon.cpp:147:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  147 |     for (auto [a, b] : tmp) {
      |               ^

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 2 ms 2644 KB Output is correct
5 Correct 2 ms 2692 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 1 ms 2644 KB Output is correct
8 Correct 2 ms 2644 KB Output is correct
9 Correct 2 ms 2676 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2684 KB Output is correct
12 Correct 2 ms 2644 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 1 ms 2684 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2688 KB Output is correct
2 Correct 1 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 440 ms 39120 KB Output is correct
5 Correct 363 ms 31488 KB Output is correct
6 Correct 394 ms 40192 KB Output is correct
7 Correct 400 ms 29884 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 403 ms 31944 KB Output is correct
2 Correct 454 ms 34560 KB Output is correct
3 Correct 313 ms 30724 KB Output is correct
4 Correct 337 ms 29936 KB Output is correct
5 Correct 418 ms 39984 KB Output is correct
6 Correct 376 ms 32864 KB Output is correct
7 Correct 345 ms 32036 KB Output is correct
8 Correct 352 ms 31856 KB Output is correct
9 Correct 368 ms 32720 KB Output is correct
10 Correct 278 ms 32780 KB Output is correct
11 Correct 2 ms 2644 KB Output is correct
12 Correct 2 ms 2644 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 2 ms 2644 KB Output is correct

Subtask #4
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2644 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 2 ms 2644 KB Output is correct
4 Correct 2 ms 2644 KB Output is correct
5 Correct 2 ms 2692 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 1 ms 2644 KB Output is correct
8 Correct 2 ms 2644 KB Output is correct
9 Correct 2 ms 2676 KB Output is correct
10 Correct 2 ms 2680 KB Output is correct
11 Correct 2 ms 2684 KB Output is correct
12 Correct 2 ms 2644 KB Output is correct
13 Correct 2 ms 2644 KB Output is correct
14 Correct 1 ms 2684 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct
16 Correct 1 ms 2688 KB Output is correct
17 Correct 1 ms 2644 KB Output is correct
18 Correct 1 ms 2644 KB Output is correct
19 Correct 440 ms 39120 KB Output is correct
20 Correct 363 ms 31488 KB Output is correct
21 Correct 394 ms 40192 KB Output is correct
22 Correct 400 ms 29884 KB Output is correct
23 Correct 403 ms 31944 KB Output is correct
24 Correct 454 ms 34560 KB Output is correct
25 Correct 313 ms 30724 KB Output is correct
26 Correct 337 ms 29936 KB Output is correct
27 Correct 418 ms 39984 KB Output is correct
28 Correct 376 ms 32864 KB Output is correct
29 Correct 345 ms 32036 KB Output is correct
30 Correct 352 ms 31856 KB Output is correct
31 Correct 368 ms 32720 KB Output is correct
32 Correct 278 ms 32780 KB Output is correct
33 Correct 2 ms 2644 KB Output is correct
34 Correct 2 ms 2644 KB Output is correct
35 Correct 2 ms 2644 KB Output is correct
36 Correct 2 ms 2644 KB Output is correct
37 Correct 446 ms 32384 KB Output is correct
38 Correct 471 ms 33620 KB Output is correct
39 Correct 445 ms 31936 KB Output is correct
40 Correct 414 ms 32884 KB Output is correct
41 Correct 458 ms 32056 KB Output is correct
42 Correct 421 ms 32796 KB Output is correct
43 Correct 416 ms 32448 KB Output is correct
44 Correct 445 ms 32756 KB Output is correct
45 Correct 408 ms 32780 KB Output is correct
46 Correct 415 ms 32928 KB Output is correct
47 Correct 383 ms 33036 KB Output is correct
48 Correct 380 ms 31856 KB Output is correct
49 Correct 426 ms 34440 KB Output is correct
50 Correct 338 ms 30696 KB Output is correct
51 Correct 378 ms 29972 KB Output is correct
52 Correct 452 ms 39916 KB Output is correct
53 Correct 463 ms 32920 KB Output is correct
54 Correct 420 ms 31992 KB Output is correct
55 Correct 369 ms 31876 KB Output is correct
56 Correct 443 ms 32676 KB Output is correct
57 Correct 300 ms 32776 KB Output is correct
58 Correct 2 ms 2644 KB Output is correct
59 Correct 2 ms 2644 KB Output is correct
60 Correct 2 ms 2644 KB Output is correct
61 Correct 2 ms 2688 KB Output is correct
62 Correct 2 ms 2644 KB Output is correct
63 Correct 2 ms 2644 KB Output is correct
64 Correct 2 ms 2680 KB Output is correct
65 Correct 435 ms 39084 KB Output is correct
66 Correct 373 ms 31544 KB Output is correct
67 Correct 370 ms 40204 KB Output is correct
68 Correct 367 ms 29880 KB Output is correct
69 Correct 2 ms 2680 KB Output is correct
70 Correct 2 ms 2688 KB Output is correct
71 Correct 2 ms 2688 KB Output is correct
72 Correct 2 ms 2644 KB Output is correct
73 Correct 2 ms 2644 KB Output is correct
74 Correct 3 ms 2680 KB Output is correct
75 Correct 2 ms 2644 KB Output is correct
76 Correct 2 ms 2644 KB Output is correct
77 Correct 2 ms 2692 KB Output is correct
78 Correct 2 ms 2692 KB Output is correct
79 Correct 3 ms 2656 KB Output is correct
80 Correct 2 ms 2692 KB Output is correct
81 Correct 2 ms 2696 KB Output is correct
82 Correct 2 ms 2684 KB Output is correct
83 Correct 2 ms 2644 KB Output is correct