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답안 #1096012

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1096012 2024-10-03T14:57:19 Z underwaterkillerwhale Logičari (COCI21_logicari) C++17
110 / 110
 45 ms 21996 KB 
#include <bits/stdc++.h>
#define ll              long long
#define pii             pair<int,int>
#define pll             pair<ll,ll>
#define rep(i,m,n)      for(int i=(m); i<=(n); i++)
#define reb(i,m,n)      for(int i=(m); i>=(n); i--)
#define iter(id, v)     for(auto id : v)
#define fs              first
#define se              second
#define MP              make_pair
#define pb              push_back
#define bit(msk, i)     ((msk >> i) & 1)
#define SZ(v)           (ll)v.size()
#define ALL(v)          v.begin(),v.end()

using namespace std;

mt19937_64 rd(chrono :: steady_clock :: now ().time_since_epoch().count());
ll Rand (ll l, ll r) { return uniform_int_distribution<ll> (l, r) (rd); }

const int N = 1e5 + 7;
const int Mod = 1e9 + 7; ///loonf mod sai
const int INF = 1e9;
const ll BASE = 137;
const int szBL = 320;

int n, m;
int a[N];
vector<int> ke[N];

int dp[N][2][2], f[N][2][2], Val[N][2][2];

vector<int> C;
int dd[N];

void Find_cycle () {
    C = {-1};
    int ok = 0;
    function<void(int, int)> dfs = [&] (int u, int p) {
        dd[u] = 1;
        C.pb(u);
        iter (&v, ke[u])
            if (v != p && !ok) {
                if (dd[v] == 1) {
                    auto R = find(C.begin() + 1, C.end(), v);
                    if (R != C.begin()) {
                        C.erase(C.begin() + 1, R);
                    }
                    ok = 1;
                    return;
                }
                dfs(v, u);
            }
        if (!ok) C.pop_back();
    };
    dfs(1, 0);
    m = SZ(C) - 1;
    rep (i, 1, n) dd[i] = 0;
    rep (i, 1, m) dd[C[i]] = 1;
}

void Assign (int u, vector<int> &child) {
    if (SZ(child) == 0) {
        f[u][1][0] = 1;
        f[u][0][0] = 0;
        return;
    }
    f[u][0][0] = 0;
    f[u][1][0] = 1;
    vector<int> vec00, vec10;
    iter (&v, child) {
        if (f[v][0][1] > n && SZ(vec00) < 2) vec00.pb(v);
        if (f[v][0][0] > n && SZ(vec10) < 2) vec10.pb(v);
        f[u][0][0] = min (INF, f[u][0][0] + f[v][0][1]);
        f[u][1][0] = min (INF, f[u][1][0] + f[v][0][0]);
    }
    auto calc = [&] (int t, int p, vector<int> &vec) {
        int nt, np, pt, pp;
        if (t == 0 && p == 1) pt = 0, pp = 1, nt = 1, np = 1;
        else pt = 0, pp = 0, nt = 1, np = 0;
        if (SZ(vec) == 1) {
            int alterV = vec[0];
            f[u][t][p] = t;
            iter (&v, child) {
                if (v != alterV) f[u][t][p] = min (INF, f[u][t][p] + f[v][pt][pp]);
                else f[u][t][p] = min (INF, f[u][t][p] + f[v][nt][np]);
            }
        }
        else if (SZ(vec) == 0) {
            int Min = INF;
            f[u][t][p] = t;
            iter (&v, child) {
                f[u][t][p] = min (INF, f[u][t][p] + f[v][pt][pp]);
                Min = min(Min, -f[v][pt][pp] + f[v][nt][np]);
            }
            f[u][t][p] = min(INF, f[u][t][p] + Min);
        }
        else f[u][t][p] = INF;
    };
    calc(0, 1, vec00);
    calc(1, 1, vec10);
}

void dfs (int u, int p) {
    vector<int> child;
    iter (&v, ke[u]) {
        if (!dd[v] && v != p) {
            dfs(v, u);
            child.pb(v);
        }
    }
    Assign(u, child);
}

int calc (int t, int p) {///con 1 trang thai nao va look con nao ben phai chua
    rep (i, 1, m)
    rep (j, 0, 1)
    rep (t, 0, 1) dp[i][j][t] = INF;
    if (t == 1 && p == 1) {
        dp[2][0][1] = min(INF, Val[1][1][1] + Val[2][0][0]);
        dp[2][1][1] = min(INF, Val[1][1][0] + Val[2][1][0]);
    }
    else if (t == 1 && p == 0) {
        dp[2][0][1] = min(INF, Val[1][1][0] + Val[2][0][0]);
    }
    else if (t == 0 && p == 1) {
        rep (i, 0, 1) {
            dp[2][0][i] = min(INF, Val[1][0][1] + Val[2][0][i]);
            dp[2][1][i] = min(INF, Val[1][0][0] + Val[2][1][i]);
        }
    }
    else {
        rep (i, 0, 1) dp[2][0][i] = min(INF, Val[1][0][0] + Val[2][0][i]);
    }

    rep (i, 3, m) {
        dp[i][0][0] = min({INF,
                          dp[i - 1][0][1] + Val[i][0][0]});
        dp[i][0][1] = min({INF,
                          dp[i - 1][0][1] + Val[i][0][1],
                          dp[i - 1][1][1] + Val[i][0][0]});
        dp[i][1][0] = min({INF,
                          dp[i - 1][0][0] + Val[i][1][0]});
        dp[i][1][1] = min({INF,
                          dp[i - 1][1][0] + Val[i][1][0],
                          dp[i - 1][0][0] + Val[i][1][1]});
    }
    if (t == 1 && p == 1)
        return dp[m][0][0];
    else if (t == 1 && p == 0)
        return dp[m][1][0];
    else if (t == 0 && p == 1)
        return dp[m][0][1];
    else
        return dp[m][1][1];
}

void solution() {
    cin >> n;
    rep (i, 1, n) {
        int u, v;
        cin >> u >> v;
        ke[u].pb(v);
        ke[v].pb(u);
    }
    Find_cycle();
    rep (i, 1, n)
    rep (j, 0, 1)
    rep (t, 0, 1)
        f[i][j][t] = INF;
    rep (i, 1, m) {
        int u = C[i];
        dfs(u, 0);
    }
    rep (i, 1, m)
    rep (j, 0, 1)
    rep (t, 0, 1) {
        Val[i][j][t] = f[C[i]][j][t];
    }
    int res = INF;
    rep (i, 0, 1)
    rep (j, 0, 1) {
        res = min(res, calc(i, j));
    }
    if (res > n)
        cout << -1 <<"\n";
    else
        cout << res <<"\n";
}

#define file(name) freopen(name".inp","r",stdin); \
freopen(name".out","w",stdout);
int main () {
//    file("c");
    ios_base :: sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int num_Test = 1;
//    cin >> num_Test;
    while (num_Test--)
        solution();
}
/*
no bug +9

*/

Subtask #1
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2648 KB Output is correct
5 Correct 41 ms 21960 KB Output is correct
6 Correct 41 ms 21884 KB Output is correct
7 Correct 42 ms 21960 KB Output is correct
8 Correct 42 ms 21996 KB Output is correct

Subtask #2
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2652 KB Output is correct
6 Correct 2 ms 2648 KB Output is correct
7 Correct 1 ms 2820 KB Output is correct
8 Correct 1 ms 2652 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2652 KB Output is correct
6 Correct 2 ms 2648 KB Output is correct
7 Correct 1 ms 2820 KB Output is correct
8 Correct 1 ms 2652 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct
13 Correct 2 ms 2652 KB Output is correct
14 Correct 1 ms 2652 KB Output is correct
15 Correct 2 ms 2652 KB Output is correct
16 Correct 2 ms 2652 KB Output is correct
17 Correct 2 ms 2648 KB Output is correct
18 Correct 2 ms 2652 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct
21 Correct 2 ms 2908 KB Output is correct
22 Correct 1 ms 2908 KB Output is correct
23 Correct 2 ms 2908 KB Output is correct
24 Correct 1 ms 2908 KB Output is correct

Subtask #4
50.0 / 50.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2648 KB Output is correct
5 Correct 41 ms 21960 KB Output is correct
6 Correct 41 ms 21884 KB Output is correct
7 Correct 42 ms 21960 KB Output is correct
8 Correct 42 ms 21996 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 2 ms 2648 KB Output is correct
15 Correct 1 ms 2820 KB Output is correct
16 Correct 1 ms 2652 KB Output is correct
17 Correct 1 ms 2652 KB Output is correct
18 Correct 1 ms 2652 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct
21 Correct 2 ms 2652 KB Output is correct
22 Correct 1 ms 2652 KB Output is correct
23 Correct 2 ms 2652 KB Output is correct
24 Correct 2 ms 2652 KB Output is correct
25 Correct 2 ms 2648 KB Output is correct
26 Correct 2 ms 2652 KB Output is correct
27 Correct 1 ms 2652 KB Output is correct
28 Correct 1 ms 2652 KB Output is correct
29 Correct 2 ms 2908 KB Output is correct
30 Correct 1 ms 2908 KB Output is correct
31 Correct 2 ms 2908 KB Output is correct
32 Correct 1 ms 2908 KB Output is correct
33 Correct 30 ms 8272 KB Output is correct
34 Correct 30 ms 8276 KB Output is correct
35 Correct 39 ms 8272 KB Output is correct
36 Correct 28 ms 8312 KB Output is correct
37 Correct 9 ms 4232 KB Output is correct
38 Correct 36 ms 8404 KB Output is correct
39 Correct 3 ms 3164 KB Output is correct
40 Correct 26 ms 8120 KB Output is correct
41 Correct 23 ms 10000 KB Output is correct
42 Correct 27 ms 9860 KB Output is correct
43 Correct 45 ms 18632 KB Output is correct
44 Correct 34 ms 14544 KB Output is correct