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Submission #745235

# Submission time Handle Problem Language Result Execution time Memory
745235 2023-05-19T15:17:41 Z Ahmed57 Magneti (COCI21_magneti) C++17
10 / 110
 27 ms 1876 KB 
#include <iostream>

using namespace std;

#define mod 1000000007

long long fact[100001],inverse[100001];

long long power(long long x,long long n)
{
    if (n == 0) {
        return 1;
    }
    long long pow = power(x, n / 2)%mod;
    if (n & 1) {
        return ((((x%mod) * (pow%mod))%mod) * pow%mod)%mod;
    }
    return ((pow%mod) * (pow%mod))%mod;
}

long long solve(int a,int b){
    return((fact[a]*inverse[b])%mod*inverse[a-b])%mod;
}
long long stars(long long a,long long b){
    return solve(a+b-b,b);
}
int main()
{
    fact[0] = inverse[0] = fact[1] = inverse[1] = 1;
    for(int i = 2;i<=1e5;i++){
        fact[i]=fact[i-1]*i;
        fact[i]%=mod;
        inverse[i] = power(fact[i],mod-2);
    }
    long long n,l,x;
    cin>>n>>l;
    for(int i = 0;i<n;i++){
        cin>>x;
    }
    if(l<(n-1)*x){
        cout<<0<<endl;
        return 0;
    }
    cout<<(stars(l-(n-1)*(x-1),n)*fact[n])%mod<<endl;
    return 0;
}

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 1748 KB Output is correct
2 Correct 27 ms 1788 KB Output is correct
3 Correct 26 ms 1740 KB Output is correct
4 Correct 27 ms 1848 KB Output is correct
5 Correct 27 ms 1848 KB Output is correct
6 Correct 26 ms 1848 KB Output is correct
7 Correct 25 ms 1728 KB Output is correct
8 Correct 25 ms 1844 KB Output is correct
9 Correct 26 ms 1752 KB Output is correct
10 Correct 26 ms 1856 KB Output is correct

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 1764 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Incorrect 26 ms 1876 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 1748 KB Output is correct
2 Correct 27 ms 1788 KB Output is correct
3 Correct 26 ms 1740 KB Output is correct
4 Correct 27 ms 1848 KB Output is correct
5 Correct 27 ms 1848 KB Output is correct
6 Correct 26 ms 1848 KB Output is correct
7 Correct 25 ms 1728 KB Output is correct
8 Correct 25 ms 1844 KB Output is correct
9 Correct 26 ms 1752 KB Output is correct
10 Correct 26 ms 1856 KB Output is correct
11 Incorrect 26 ms 1764 KB Output isn't correct
12 Halted 0 ms 0 KB -