//ᗜˬᗜ
#include<bits/stdc++.h>
#define int long long
#define vi vector <int>
#define bs binary_search
#define lb lower_bound
#define ub upper_bound
#define pb emplace_back
#define fu(i, a, b) for(int i = (a); i < (b); i++)
#define fub(i, a, b) for(int i = (a); i <= (b); i++)
#define pii pair<int, int>
#define fastio ios_base::sync_with_stdio(0); cin.tie(0);
using namespace std;
const int lim = 1e18;
const int N = 1e6 + 3;
const int M = 1e9 + 7;
int n, k, res;
int a[N], mp[N];
int expo(int a, int b){
if(b == 0)return 1;
if(b%2 == 0)return expo((a*a)%M, b/2)%M;
return (a*expo((a*a)%M, b/2))%M;
}
int bico(int n, int k){
if(k > n or n < 0 or k < 0)return 0;
int res = 1;
fub(i, k+1, n)res = (res*i)%M;
fub(i, 1, n-k)res = (res*expo(i, N-2))%M;
return res;
}
signed main(){
fastio;
cin >> n >> k;
fub(i, 1, n-k+1)cin >> a[i];
memset(mp, -1, sizeof(mp));
fub(i, 2, n-k+1){
if(abs(a[i] - a[i-1]) > 1){
cout << 0;
return 0;
}
}
fub(i, 2, n-k+1){
if(a[i] - a[i-1] == 1){
mp[i+k-1] = 1; mp[i-1] = 0;
}
else if(a[i] - a[i-1] == -1){
mp[i+k-1] = 0; mp[i-1] = 1;
}
else mp[i+k-1] = mp[i-1];
}
for(int i = n-k; i >= 1; i--)if(a[i] == a[i+1])mp[i] = mp[i+k];
fub(i, 1, k){
res += (mp[i] == -1);
a[1] -= (mp[i] == 1);
}
cout << bico(res, a[1]);
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
1 ms |
8796 KB |
Output is correct |
6 |
Correct |
1 ms |
8796 KB |
Output is correct |
7 |
Incorrect |
1 ms |
8796 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |