Submission #932337

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
932337	2024-02-23T08:24:49 Z	LucaIlie	Star Trek (CEOI20_startrek)	C++17	23 / 100	1000 ms	16468 KB

startrek

#include <bits/stdc++.h>

#define int long long

using namespace std;

const int MAX_N = 1e5;
const int MAX_D = 1e5;
const int MOD = 1e9 + 7;
bool canWin[MAX_N + 1];
int countChildrenLosers[MAX_N + 1], add[MAX_N + 1], reach[MAX_N + 1], dp[MAX_D];
vector<int> adj[MAX_N + 1];

void dfsGame( int u, int p ) {
    canWin[u] = false;
    countChildrenLosers[u] = 0;
    for ( int v: adj[u] ) {
        if ( v == p )
            continue;
        dfsGame( v, u );
        canWin[u] |= (!canWin[v]);
        countChildrenLosers[u] += (!canWin[v]);
    }
}

void dfsCalcAdd( int u, int p ) {
    if ( p == 0 ) {
        add[u] = (canWin[u] ? -1 : 1);
        reach[u] = u;
    } else {
        if ( canWin[u] ) {
            if ( canWin[p] ) {
                add[u] = -1;
                reach[u] = u;
            } else {
                add[u] = add[p] - 1;
                reach[u] = reach[p];
            }
        } else {
            if ( countChildrenLosers[p] >= 2 ) {
                add[u] = 1;
                reach[u] = u;
            } else {
                add[u] = add[p] + 1;
                reach[u] = reach[p];
            }
        }
    }

    for ( int v: adj[u] ) {
        if ( v == p )
            continue;
        dfsCalcAdd( v, u );
    }
}

int lgPut( int x, int n ) {
    if ( n == 0 )
        return 1;

    int p = lgPut( x, n / 2 );
    p = (long long)p * p % MOD;
    if ( n % 2 == 1 )
        p = (long long)p * x % MOD;

    return p;
}

signed main() {
    int n, d;

    cin >> n >> d;

    for ( int i = 0; i < n - 1; i++ ) {
        int u, v;
        cin >> u >> v;
        adj[u].push_back( v );
        adj[v].push_back( u );
        /*adj[u + n].push_back( v + n );
        adj[v + n].push_back( u + n );
        adj[u + 2 * n].push_back( v + 2 * n );
        adj[v + 2 * n].push_back( u + 2 * n );*/
    }

    /*int an = 0;
    for ( int u = 1; u <= n; u++ ) {
        for ( int v = n + 1; v <= 2 * n; v++ ) {
            adj[u].push_back( v );
            adj[v].push_back( u );
            for ( int w = n + 1; w <= 2 * n; w++ ) {
                for ( int t = 2 * n + 1; t <= 3 * n; t++ ) {
                    adj[w].push_back( t );
                    adj[t].push_back( w );
                    dfsGame( 1, 0 );
                    if ( canWin[1] ) {
                        an++;
                        printf( "W %d-%d %d-%d\n", u, v, w, t );
                    }
                    adj[w].pop_back();
                    adj[t].pop_back();
                }
            }
            adj[u].pop_back();
            adj[v].pop_back();
        }
    }
    cout << an << "\n";*/

    int losers = 0, winners = 0, reach1Losers = 0, reach1Winners = 0;
    for ( int r = 1; r <= n; r++ ) {
        dfsGame( r, 0 );
        dfsCalcAdd( r, 0 );
        losers += !canWin[r];
        winners += canWin[r];
        for ( int v = 1; v <= n; v++ ) {
            reach1Losers += (!canWin[r] && !canWin[v] && reach[v] == 1);
            reach1Winners += (canWin[r] && !canWin[v] && reach[v] == 1);
        }
    }

    dp[0] = losers;
    for ( int i = 1; i < d; i++ )
        dp[i] = (losers * lgPut( n, 2 * d ) + (reach1Winners - reach1Losers + MOD) * dp[i - 1]) % MOD;

    dfsGame( 1, 0 );
    dfsCalcAdd( 1, 0 );

    int ans = (canWin[1] ? 0 : lgPut( n, 2 * d ) );
    for ( int v = 1; v <= n; v++ ) {
        if ( canWin[1] ) {
            if ( !canWin[v] && reach[v] == 1 )
                ans = (ans + dp[d - 1]) % MOD;
        } else {
            if ( !canWin[v] && reach[v] == 1 )
                ans = (ans - dp[d - 1]) % MOD;
        }
    }

    cout << (lgPut( n, 2 * d ) - ans + MOD) % MOD << "\n";

    return 0;
}

Subtask #1
0.0 / 0.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	4952 KB	Output is correct
2	Incorrect	18 ms	4696 KB	Output isn't correct
3	Halted	0 ms	0 KB	-

Subtask #2
0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4700 KB	Output is correct
2	Correct	2 ms	4700 KB	Output is correct
3	Runtime error	135 ms	11620 KB	Execution killed with signal 11
4	Halted	0 ms	0 KB	-

Subtask #3
8.0 / 8.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4716 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct

Subtask #4
15.0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4716 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct
7	Correct	24 ms	4696 KB	Output is correct
8	Correct	30 ms	4696 KB	Output is correct
9	Correct	16 ms	4700 KB	Output is correct
10	Correct	23 ms	4780 KB	Output is correct
11	Correct	24 ms	4700 KB	Output is correct

Subtask #5
0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4716 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct
7	Correct	24 ms	4696 KB	Output is correct
8	Correct	30 ms	4696 KB	Output is correct
9	Correct	16 ms	4700 KB	Output is correct
10	Correct	23 ms	4780 KB	Output is correct
11	Correct	24 ms	4700 KB	Output is correct
12	Execution timed out	1050 ms	16468 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #6
0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4716 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct
7	Correct	24 ms	4696 KB	Output is correct
8	Correct	30 ms	4696 KB	Output is correct
9	Correct	16 ms	4700 KB	Output is correct
10	Correct	23 ms	4780 KB	Output is correct
11	Correct	24 ms	4700 KB	Output is correct
12	Correct	1 ms	4700 KB	Output is correct
13	Incorrect	18 ms	4776 KB	Output isn't correct
14	Halted	0 ms	0 KB	-

Subtask #7
0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	4716 KB	Output is correct
2	Correct	1 ms	4696 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct
7	Correct	24 ms	4696 KB	Output is correct
8	Correct	30 ms	4696 KB	Output is correct
9	Correct	16 ms	4700 KB	Output is correct
10	Correct	23 ms	4780 KB	Output is correct
11	Correct	24 ms	4700 KB	Output is correct
12	Execution timed out	1050 ms	16468 KB	Time limit exceeded
13	Halted	0 ms	0 KB	-

Subtask #8
0 / 15.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	4952 KB	Output is correct
2	Incorrect	18 ms	4696 KB	Output isn't correct
3	Halted	0 ms	0 KB	-

Submission #932337

Compilation message