oj.uz

답안 #723074

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
723074 2023-04-13T08:18:30 Z 0__0 Bi-ing Lottery Treekets (CCO22_day2problem1) C++17
16 / 25
 55 ms 32552 KB 
#include "bits/stdc++.h"

using namespace std;

void abc() {cout << endl;}
template <typename T, typename ...U> void abc(T a, U ...b) {
    cout << a << ' ', abc(b...);
}
template <typename T> void printv(T l, T r) {
    while (l != r) cout << *l << " \n"[++l == r];
}
template <typename A, typename B> istream& operator >> (istream& o, pair<A, B> &a) {
    return o >> a.first >> a.second;
}
template <typename A, typename B> ostream& operator << (ostream& o, pair<A, B> a) {
    return o << '(' << a.first << ", " << a.second << ')';
}
template <typename T> ostream& operator << (ostream& o, vector<T> a) {
    bool is = false;
    for (T i : a) {o << (is ? ' ' : '{'), is = true, o << i;}
    return o << '}';
}

#ifdef local
#define test(args...) abc("[" + string(#args) + "]", args)
#else
#define test(args...) void(0)
#endif

using ll = long long;

#define int ll

int loc[4005];
int lpar[4005], rpar[4005];
ll dp[4005][4005]; // at node i, need j balls from above
int above[4005]; //exclusive
int below[4005]; //inclusive
int sz[4005];

const ll MOD = 1e9 + 7;

ll factorial[4005];
ll inverse[4005];
ll inversef[4005];

ll choose(int a, int b) {
    if (a < b) return 0;
    return ((factorial[a] % MOD * inversef[b] % MOD) % MOD) * (inversef[a - b]) % MOD;
}

void dfs(int node, int par = -1, bool left = true) {

    below[node] = loc[node];
    sz[node] = 1;

    if (lpar[node]) {
        above[lpar[node]] = above[node] + loc[node];
        dfs(lpar[node], node, true);
        below[node] += below[lpar[node]];
        sz[node] += sz[lpar[node]];
    }
    if (rpar[node]) {
        above[rpar[node]] = above[node] + loc[node];
        dfs(rpar[node], node, false);
        below[node] += below[rpar[node]];
        sz[node] += sz[rpar[node]];
    }

    if (sz[node] < below[node]) {
        cout << 0 << '\n';
        exit(0);
    }


//    if (lpar[node] ==0  && rpar[node] == 0) {
//        if (loc[node] > 1) {
//            cout << 0 << "\n";
//            exit(0);
//        }
//
//        if (lpar[node] || rpar[node]) {
//            dp[node][0] = 1;
//        } else {
//            dp[node][1] = 1;
//        }
//
//        return;
//    }

    int lc = lpar[node];
    int rc = rpar[node];
    int leftsz = sz[lc] - below[lc];
    int rightsz = sz[rc] - below[rc];
    int lefttaken = below[lc];
    int righttaken = below[rc];
    int space = sz[node] - lefttaken - righttaken;

    if (!left) {
        swap(lc, rc);
        swap(leftsz, rightsz);
        swap(lefttaken, righttaken);
    }

    // the root is somewhere else
    {
        for (int take = 0; take <= leftsz && take <= loc[node]; take++) {
            int takeo = loc[node] - take;

            if (takeo > rightsz) continue;

            for (int i = 0; i <= above[node] && i + loc[node] <= space; i++) {
                int amtleft = min(leftsz, take + i);
                int remain = take + i - amtleft;
                int amtright = min(rightsz, remain + takeo);

                if (amtleft + amtright < loc[node]) continue;

                ll constant = 1;

                if (loc[node] + i == amtleft + amtright + 1) {
                    constant = choose(loc[node], take) % MOD;
                    constant = (constant * choose(i, amtleft - take) % MOD * choose(i - (amtleft - take), 1));
                } else {
                    constant = choose(loc[node], take) % MOD;
                    constant = (constant % MOD * choose(i, amtleft - take));
                }

                dp[node][i] = (dp[node][i] + ((dp[lc][amtleft] * dp[rc][amtright]) % MOD) * constant) % MOD;
            }
        }
    }

    // take root with itself
    {
        for (int take = 0; take <= leftsz && take < loc[node]; take++) {
            int takeo = loc[node] - take - 1;
            if (takeo > rightsz) continue;

            for (int i = 0; i <= above[node] && i + loc[node] <= space; i++) {

                int amtleft = min(leftsz, take + i);
                int remain = take + i - amtleft;
                int amtright = min(rightsz, remain + takeo);

                if (amtleft + amtright + 1 < loc[node]) continue;

                if (i + loc[node] != space) {
                    continue;
                }

                ll constant;

                if (loc[node] + i == amtleft + amtright + 1) {
                    constant = (choose(loc[node], take) * choose(loc[node] - take, takeo)) % MOD;
                    constant = (constant * choose(i, amtleft - take)) % MOD;
                } else {
                    constant = choose(loc[node], take) % MOD;
                    constant = (constant * choose(i, amtleft - take));
                }

                dp[node][i] = (dp[node][i] + ((dp[lc][amtleft] * dp[rc][amtright]) % MOD) * constant) % MOD;
            }
        }
    }
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
//    freopen("", "r", stdin);
//    freopen("", "w", stdout);
    int n, k; cin >> n >> k;
    factorial[0] = 1;
    for (int i = 1; i <= 4004; i++) {
        factorial[i] = (factorial[i - 1] * i) % MOD;
    }

    inverse[0] = 1;
    inverse[1] = 1;
    for (int i = 2; i <= 4004; i++) {
        inverse[i] = MOD - (MOD / i) * inverse[MOD % i] % MOD;
    }

    inversef[0] = 1;
    for (int i = 1; i <= 4004; i++) {
        inversef[i] = (inversef[i-1] * inverse[i]) % MOD;
    }

    if (k > n) {
        cout << "0\n";
        exit(0);
    }
    for (int i = 1; i <= k; i++) {
        int t; cin >> t;
        loc[t]++;
    }
    for (int i = 1; i <= n; i++) cin >> lpar[i] >> rpar[i];

    dp[0][0] = 1;
    dfs(1);

    cout << dp[1][0] % MOD << "\n";
}

Subtask #1
3.0 / 3.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct

Subtask #2
4.0 / 4.0

# 결과 실행 시간 메모리 Grader output
1 Correct 13 ms 17492 KB Output is correct
2 Correct 55 ms 32552 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 2 ms 1236 KB Output is correct
5 Correct 1 ms 1364 KB Output is correct
6 Correct 13 ms 17492 KB Output is correct
7 Correct 39 ms 26116 KB Output is correct
8 Correct 17 ms 19052 KB Output is correct
9 Correct 37 ms 24316 KB Output is correct
10 Correct 21 ms 20364 KB Output is correct
11 Correct 51 ms 31352 KB Output is correct
12 Correct 1 ms 372 KB Output is correct
13 Correct 31 ms 24124 KB Output is correct
14 Correct 46 ms 29452 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 13 ms 17620 KB Output is correct
17 Correct 32 ms 23884 KB Output is correct

Subtask #3
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 12 ms 16776 KB Output is correct
2 Correct 13 ms 17492 KB Output is correct
3 Correct 13 ms 16852 KB Output is correct
4 Correct 13 ms 16852 KB Output is correct
5 Correct 14 ms 16820 KB Output is correct
6 Correct 12 ms 16936 KB Output is correct
7 Correct 11 ms 16852 KB Output is correct
8 Correct 11 ms 17000 KB Output is correct
9 Correct 15 ms 16852 KB Output is correct
10 Correct 12 ms 17280 KB Output is correct
11 Correct 11 ms 16852 KB Output is correct
12 Correct 20 ms 19172 KB Output is correct
13 Correct 13 ms 17104 KB Output is correct
14 Correct 12 ms 16760 KB Output is correct
15 Correct 14 ms 16852 KB Output is correct
16 Correct 12 ms 16980 KB Output is correct
17 Correct 11 ms 16852 KB Output is correct
18 Correct 15 ms 17280 KB Output is correct
19 Correct 12 ms 16852 KB Output is correct
20 Correct 7 ms 8660 KB Output is correct
21 Correct 13 ms 15956 KB Output is correct
22 Correct 11 ms 16612 KB Output is correct
23 Correct 10 ms 16340 KB Output is correct
24 Correct 11 ms 16724 KB Output is correct
25 Correct 10 ms 15060 KB Output is correct
26 Correct 11 ms 16724 KB Output is correct
27 Correct 10 ms 15956 KB Output is correct
28 Correct 12 ms 16468 KB Output is correct

Subtask #4
0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 468 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct
20 Correct 13 ms 17492 KB Output is correct
21 Correct 55 ms 32552 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 2 ms 1236 KB Output is correct
24 Correct 1 ms 1364 KB Output is correct
25 Correct 13 ms 17492 KB Output is correct
26 Correct 39 ms 26116 KB Output is correct
27 Correct 17 ms 19052 KB Output is correct
28 Correct 37 ms 24316 KB Output is correct
29 Correct 21 ms 20364 KB Output is correct
30 Correct 51 ms 31352 KB Output is correct
31 Correct 1 ms 372 KB Output is correct
32 Correct 31 ms 24124 KB Output is correct
33 Correct 46 ms 29452 KB Output is correct
34 Correct 1 ms 340 KB Output is correct
35 Correct 13 ms 17620 KB Output is correct
36 Correct 32 ms 23884 KB Output is correct
37 Correct 12 ms 16776 KB Output is correct
38 Correct 13 ms 17492 KB Output is correct
39 Correct 13 ms 16852 KB Output is correct
40 Correct 13 ms 16852 KB Output is correct
41 Correct 14 ms 16820 KB Output is correct
42 Correct 12 ms 16936 KB Output is correct
43 Correct 11 ms 16852 KB Output is correct
44 Correct 11 ms 17000 KB Output is correct
45 Correct 15 ms 16852 KB Output is correct
46 Correct 12 ms 17280 KB Output is correct
47 Correct 11 ms 16852 KB Output is correct
48 Correct 20 ms 19172 KB Output is correct
49 Correct 13 ms 17104 KB Output is correct
50 Correct 12 ms 16760 KB Output is correct
51 Correct 14 ms 16852 KB Output is correct
52 Correct 12 ms 16980 KB Output is correct
53 Correct 11 ms 16852 KB Output is correct
54 Correct 15 ms 17280 KB Output is correct
55 Correct 12 ms 16852 KB Output is correct
56 Correct 7 ms 8660 KB Output is correct
57 Correct 13 ms 15956 KB Output is correct
58 Correct 11 ms 16612 KB Output is correct
59 Correct 10 ms 16340 KB Output is correct
60 Correct 11 ms 16724 KB Output is correct
61 Correct 10 ms 15060 KB Output is correct
62 Correct 11 ms 16724 KB Output is correct
63 Correct 10 ms 15956 KB Output is correct
64 Correct 12 ms 16468 KB Output is correct
65 Correct 10 ms 15248 KB Output is correct
66 Correct 11 ms 16852 KB Output is correct
67 Correct 11 ms 15636 KB Output is correct
68 Incorrect 11 ms 17108 KB Output isn't correct
69 Halted 0 ms 0 KB -