oj.uz

Submission #602777

# Submission time Handle Problem Language Result Execution time Memory
602777 2022-07-23T11:10:46 Z boris_mihov The Xana coup (BOI21_xanadu) C++14
100 / 100
 190 ms 89364 KB 
#include <iostream>
#include <vector>

typedef long long llong;
const int MAXN = 100000 + 10;
const int INF  = 1e9;

int dp[MAXN][2][2][2];
bool bl[MAXN][2][2][2];
std::vector <int> g[MAXN];
std::vector <int> dp2[MAXN][2][2][2][2];
bool state[MAXN];
int n;

int f(int node, int p, bool should, bool incoming, bool currTurned)
{
    if (g[node].size() - (p != 0) == 0)
    {
        if ((incoming ^ should) != state[node]) return INF;
        return should;
    }

    if (bl[node][should][incoming][currTurned]) 
    {
        return dp[node][should][incoming][currTurned];
    }

    bl[node][should][incoming][currTurned] = true;
    if (should)
    {
        return dp[node][should][incoming][currTurned] = f(node, p, 0, incoming, 1) + 1;
    }

    dp2[node][should][incoming][currTurned][0].resize(g[node].size() - (p != 0) + 1);
    dp2[node][should][incoming][currTurned][1].resize(g[node].size() - (p != 0) + 1);

    for (int &i : g[node])
    {
        if (i == p)
        {
            std::swap(i, g[node].back());
            break;
        }
    }

    bool wantedParity = currTurned ^ incoming ^ state[node];
    dp2[node][should][incoming][currTurned][wantedParity][g[node].size() - (p != 0)] = 0;
    dp2[node][should][incoming][currTurned][!wantedParity][g[node].size() - (p != 0)] = INF;
    
    for (int i = g[node].size() - 1 - (p != 0) ; i >= 0 ; --i)
    {
        for (int parity = 0 ; parity < 2 ; ++parity)
        {
            dp2[node][should][incoming][currTurned][parity][i] = std::min(INF, dp2[node][should][incoming][currTurned][parity][i + 1] + f(g[node][i], node, 0, currTurned, 0));
            dp2[node][should][incoming][currTurned][parity][i] = std::min(dp2[node][should][incoming][currTurned][parity][i],
                                                              dp2[node][should][incoming][currTurned][!parity][i + 1] + f(g[node][i], node, 1, currTurned, 0));
        }
    }

    return dp[node][should][incoming][currTurned] = dp2[node][should][incoming][currTurned][0][0];
}

void solve()
{
   int res = std::min(f(1, 0, 0, 0, 0), f(1, 0, 1, 0, 0));
   if (res >= MAXN) std::cout << "impossible\n";
   else std::cout << res << '\n';
}

void read()
{
    int x, y;
    std::cin >> n;
    for (int i = 2 ; i <= n ; ++i)
    {
        std::cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    
    for (int i = 1 ; i <= n ; ++i)
    {
        std::cin >> state[i];
    }
}

void fastIO()
{
    std::ios_base :: sync_with_stdio(0);
    std::cout.tie(nullptr);
    std::cin.tie(nullptr);
}

int main()
{
    fastIO();
    read();
    solve();
    
    return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 40152 KB Output is correct
2 Correct 20 ms 40148 KB Output is correct
3 Correct 22 ms 40252 KB Output is correct
4 Correct 21 ms 40260 KB Output is correct
5 Correct 20 ms 40256 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 40152 KB Output is correct
2 Correct 20 ms 40148 KB Output is correct
3 Correct 22 ms 40252 KB Output is correct
4 Correct 21 ms 40260 KB Output is correct
5 Correct 20 ms 40256 KB Output is correct
6 Correct 24 ms 40140 KB Output is correct
7 Correct 21 ms 40200 KB Output is correct
8 Correct 21 ms 40148 KB Output is correct
9 Correct 20 ms 40236 KB Output is correct
10 Correct 21 ms 40252 KB Output is correct
11 Correct 20 ms 40264 KB Output is correct
12 Correct 21 ms 40148 KB Output is correct
13 Correct 23 ms 40172 KB Output is correct
14 Correct 20 ms 40272 KB Output is correct
15 Correct 21 ms 40232 KB Output is correct
16 Correct 21 ms 40224 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 190 ms 87836 KB Output is correct
2 Correct 153 ms 87148 KB Output is correct
3 Correct 152 ms 87996 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 165 ms 87808 KB Output is correct
2 Correct 151 ms 87200 KB Output is correct
3 Correct 150 ms 88048 KB Output is correct
4 Correct 129 ms 60432 KB Output is correct
5 Correct 148 ms 63656 KB Output is correct
6 Correct 147 ms 64176 KB Output is correct
7 Correct 21 ms 40396 KB Output is correct
8 Correct 60 ms 49308 KB Output is correct
9 Correct 168 ms 67228 KB Output is correct
10 Correct 170 ms 67640 KB Output is correct
11 Correct 164 ms 68732 KB Output is correct
12 Correct 167 ms 69756 KB Output is correct
13 Correct 127 ms 59908 KB Output is correct
14 Correct 143 ms 61188 KB Output is correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 40152 KB Output is correct
2 Correct 20 ms 40148 KB Output is correct
3 Correct 22 ms 40252 KB Output is correct
4 Correct 21 ms 40260 KB Output is correct
5 Correct 20 ms 40256 KB Output is correct
6 Correct 24 ms 40140 KB Output is correct
7 Correct 21 ms 40200 KB Output is correct
8 Correct 21 ms 40148 KB Output is correct
9 Correct 20 ms 40236 KB Output is correct
10 Correct 21 ms 40252 KB Output is correct
11 Correct 20 ms 40264 KB Output is correct
12 Correct 21 ms 40148 KB Output is correct
13 Correct 23 ms 40172 KB Output is correct
14 Correct 20 ms 40272 KB Output is correct
15 Correct 21 ms 40232 KB Output is correct
16 Correct 21 ms 40224 KB Output is correct
17 Correct 190 ms 87836 KB Output is correct
18 Correct 153 ms 87148 KB Output is correct
19 Correct 152 ms 87996 KB Output is correct
20 Correct 165 ms 87808 KB Output is correct
21 Correct 151 ms 87200 KB Output is correct
22 Correct 150 ms 88048 KB Output is correct
23 Correct 129 ms 60432 KB Output is correct
24 Correct 148 ms 63656 KB Output is correct
25 Correct 147 ms 64176 KB Output is correct
26 Correct 21 ms 40396 KB Output is correct
27 Correct 60 ms 49308 KB Output is correct
28 Correct 168 ms 67228 KB Output is correct
29 Correct 170 ms 67640 KB Output is correct
30 Correct 164 ms 68732 KB Output is correct
31 Correct 167 ms 69756 KB Output is correct
32 Correct 127 ms 59908 KB Output is correct
33 Correct 143 ms 61188 KB Output is correct
34 Correct 21 ms 40260 KB Output is correct
35 Correct 21 ms 40148 KB Output is correct
36 Correct 22 ms 40224 KB Output is correct
37 Correct 20 ms 40148 KB Output is correct
38 Correct 20 ms 40236 KB Output is correct
39 Correct 24 ms 40264 KB Output is correct
40 Correct 23 ms 40220 KB Output is correct
41 Correct 21 ms 40252 KB Output is correct
42 Correct 22 ms 40164 KB Output is correct
43 Correct 20 ms 40148 KB Output is correct
44 Correct 21 ms 40372 KB Output is correct
45 Correct 146 ms 89076 KB Output is correct
46 Correct 152 ms 88488 KB Output is correct
47 Correct 156 ms 89364 KB Output is correct
48 Correct 132 ms 61592 KB Output is correct
49 Correct 142 ms 63712 KB Output is correct
50 Correct 162 ms 64224 KB Output is correct
51 Correct 21 ms 40396 KB Output is correct
52 Correct 68 ms 49304 KB Output is correct
53 Correct 159 ms 67144 KB Output is correct
54 Correct 159 ms 67660 KB Output is correct
55 Correct 167 ms 68732 KB Output is correct
56 Correct 172 ms 69704 KB Output is correct
57 Correct 134 ms 60064 KB Output is correct
58 Correct 126 ms 61220 KB Output is correct
59 Correct 58 ms 48348 KB Output is correct
60 Correct 137 ms 62032 KB Output is correct
61 Correct 156 ms 64216 KB Output is correct
62 Correct 149 ms 64684 KB Output is correct
63 Correct 149 ms 64716 KB Output is correct
64 Correct 156 ms 64664 KB Output is correct
65 Correct 95 ms 52428 KB Output is correct
66 Correct 74 ms 52528 KB Output is correct
67 Correct 68 ms 48324 KB Output is correct
68 Correct 68 ms 48324 KB Output is correct
69 Correct 69 ms 48324 KB Output is correct
70 Correct 93 ms 48384 KB Output is correct