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Submission #974076

# Submission time Handle Problem Language Result Execution time Memory
974076 2024-05-02T18:04:48 Z VinhLuu Magneti (COCI21_magneti) C++17
110 / 110
 124 ms 8788 KB 
#include <bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define pb push_back
using namespace std;

typedef pair<int,int> pii;
const int N = 1e4 + 5;
const int mod = 1e9 + 7;

int n, l, ft[N], inv[N], f[2][55][N], ans, a[N];

void get(int &x,int y){
    x = (x + y) % mod;
}

int lt(int u,int v){
    if(v == 0) return 1;
    int x = u;
    int kq = 1;
    while(v){
        if(v & 1) kq = kq * x % mod;
        x = x * x % mod;
        v /= 2;
    }
    return kq;
}

void pre(){
    int full = 1e4;
    ft[0] = 1;
    inv[0] = 1;
    for(int i = 1; i <= full; i ++){
        ft[i] = ft[i - 1] * i % mod;
        inv[i] = inv[i - 1] * lt(i, mod - 2) % mod;
    }
}

int C(int u,int v){
    if(u == v || u == 0) return 1;
    return ft[v] * inv[v - u] % mod * inv[u] % mod;
}

void sub1(){
    int d = (n - 1) * a[1] + 1;
    cout << ft[n] * C(n, l - d + n) % mod;
}

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    #define task "v"
    if(fopen(task ".inp","r")){
        freopen(task ".inp","r",stdin);
        freopen(task ".out","w",stdout);
    }
    pre();
    cin >> n >> l;
    for(int i = 1; i <= n; i ++) cin >> a[i];
    sort(a + 1, a + n + 1);
    if(a[n] == a[1]){
        sub1();
        return 0;
    }
    int pre = 0, nx = 1;
    f[0][0][0] = 1;
    for(int i = 1; i <= n; i ++){
        f[nx][0][0] = 0;
        for(int j = 1; j <= i; j ++){
            for(int k = 1; k <= l; k ++){
                f[nx][j][k] = f[pre][j - 1][k - 1];
                if(k >= a[i]) get(f[nx][j][k], f[pre][j][k - a[i]] * j % mod * 2 % mod);
                if(k >= 2 * a[i] - 1) get(f[nx][j][k], f[pre][j + 1][k - 2 * a[i] + 1] * j % mod * (j + 1) % mod);

//                cout << pre << " " << nx << " " << i << " " << j << " " << k << " " << f[nx][j][k] << " f\n";
            }
        }
        swap(pre, nx);
    }
    for(int i = 1; i <= l; i ++){
//        cout << 1 << " " << i << " " << f[pre][1][i] << " g\n";
        get(ans, f[pre][1][i] * C(n, l - i + n) % mod);
    }
    cout << ans;
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:55:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |         freopen(task ".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:56:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   56 |         freopen(task ".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 856 KB Output is correct
6 Correct 2 ms 604 KB Output is correct
7 Correct 2 ms 600 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 500 KB Output is correct
10 Correct 2 ms 604 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 3420 KB Output is correct
2 Correct 2 ms 2648 KB Output is correct
3 Correct 7 ms 3420 KB Output is correct
4 Correct 3 ms 2908 KB Output is correct
5 Correct 7 ms 3420 KB Output is correct
6 Correct 3 ms 2908 KB Output is correct
7 Correct 6 ms 3420 KB Output is correct
8 Correct 2 ms 2652 KB Output is correct
9 Correct 2 ms 2652 KB Output is correct
10 Correct 2 ms 604 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2652 KB Output is correct
2 Correct 2 ms 2568 KB Output is correct
3 Correct 3 ms 2904 KB Output is correct
4 Correct 2 ms 2908 KB Output is correct
5 Correct 3 ms 2908 KB Output is correct
6 Correct 2 ms 2620 KB Output is correct
7 Correct 4 ms 2908 KB Output is correct
8 Correct 2 ms 2648 KB Output is correct
9 Correct 2 ms 2652 KB Output is correct
10 Correct 3 ms 2652 KB Output is correct

Subtask #4
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 856 KB Output is correct
6 Correct 2 ms 604 KB Output is correct
7 Correct 2 ms 600 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 500 KB Output is correct
10 Correct 2 ms 604 KB Output is correct
11 Correct 7 ms 3420 KB Output is correct
12 Correct 2 ms 2648 KB Output is correct
13 Correct 7 ms 3420 KB Output is correct
14 Correct 3 ms 2908 KB Output is correct
15 Correct 7 ms 3420 KB Output is correct
16 Correct 3 ms 2908 KB Output is correct
17 Correct 6 ms 3420 KB Output is correct
18 Correct 2 ms 2652 KB Output is correct
19 Correct 2 ms 2652 KB Output is correct
20 Correct 2 ms 604 KB Output is correct
21 Correct 3 ms 2652 KB Output is correct
22 Correct 2 ms 2568 KB Output is correct
23 Correct 3 ms 2904 KB Output is correct
24 Correct 2 ms 2908 KB Output is correct
25 Correct 3 ms 2908 KB Output is correct
26 Correct 2 ms 2620 KB Output is correct
27 Correct 4 ms 2908 KB Output is correct
28 Correct 2 ms 2648 KB Output is correct
29 Correct 2 ms 2652 KB Output is correct
30 Correct 3 ms 2652 KB Output is correct
31 Correct 120 ms 8436 KB Output is correct
32 Correct 74 ms 6472 KB Output is correct
33 Correct 122 ms 8440 KB Output is correct
34 Correct 26 ms 4184 KB Output is correct
35 Correct 119 ms 8392 KB Output is correct
36 Correct 9 ms 3416 KB Output is correct
37 Correct 121 ms 8460 KB Output is correct
38 Correct 21 ms 3676 KB Output is correct
39 Correct 120 ms 8532 KB Output is correct
40 Correct 37 ms 4944 KB Output is correct
41 Correct 116 ms 8300 KB Output is correct
42 Correct 2 ms 2648 KB Output is correct
43 Correct 124 ms 8788 KB Output is correct
44 Correct 14 ms 3420 KB Output is correct
45 Correct 118 ms 8516 KB Output is correct
46 Correct 2 ms 2648 KB Output is correct
47 Correct 12 ms 8280 KB Output is correct
48 Correct 6 ms 7276 KB Output is correct
49 Correct 3 ms 2908 KB Output is correct
50 Correct 2 ms 2652 KB Output is correct