// Do easier subtasks for ALL problems in IO when stuck for too long
// Don't do nothing, do something, you can do it! :)
// Try a different approach, check every approach if feasible
// Don't overthink, don't panic, clear your mind
#include<bits/stdc++.h>
#define fastcincout ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define fi first
#define se second
#define pri priority_queue
#define str string
#define int long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pu push_back
#define po pop_back
#define all(v) v.begin(), v.end()
#define MOD 1000003
using namespace std;
const int N=1e6+5;
bool debug=0;
int n, k;
int fact[N], inv[N], a[N];
int mult(int x, int y) {
return (x*y)%MOD;
}
int pang(int x, int y) {
if (y == 0) return 1;
int t = pang(x, y/2);
t = mult(t, t);
if (y&1) return mult(t, x);
return t;
}
void prec() {
fact[0] = 1;
inv[0] = 1;
for (int i=1; i<=N-5; i++) {
fact[i] = mult(fact[i-1], i);
inv[i] = pang(fact[i], MOD-2);
}
}
int C(int M, int R) {
if (R < 0) return 0; // impossible
if (R > M) return 0;
return mult(fact[M], mult(inv[R], inv[M-R]));
}
void solve() {
prec();
if (debug) for (int i=1; i<=20; i++) {
cout << i << "! -> " << fact[i] << " inv: " << inv[i] << endl;
}
cin >> n >> k;
int m = n - k + 1;
for (int i=1; i<=m; i++) cin >> a[i];
int ones = 0, slots = k;
for (int i=2; i<=min(m, k); i++) {
if (abs(a[i] - a[i-1]) > 1) {
cout << 0 << "\n";
return;
}
if (a[i] > a[i-1]) {
slots--;
continue;
}
if (a[i] < a[i-1]) {
slots--;
ones++;
continue;
}
}
int ans = 0;
if (debug) cout << "Empty slots: " << slots << " ones: " << ones << "\n";
if (m == k) {
// there is one ambiguous digit
// so check
if (debug) cout << "Ambiguous!" << "\n";
slots--;
int tmp1 = C(slots, a[1]-ones), tmp2 = C(slots, a[1]-ones-1);
if (debug) cout << "+C(" << slots << ", " << a[1]-ones << ") -> " << tmp1 << "\n";
if (debug) cout << "+C(" << slots << ", " << a[1]-ones-1 << ") -> " << tmp2 << "\n";
ans += tmp1 + tmp2;
}
else {
// every digit has a pair
if (debug) cout << "All clear!" << "\n";
ans += C(slots, a[1]-ones);
}
cout << ans << "\n";
}
signed main() {
// freopen("Input.in", "r", stdin);
// freopen("Output.out", "w", stdout);
// freopen must have the file in the same folder as the code file
fastcincout;
int testcases=1;
// cin >> testcases;
while(testcases--)
{
solve();
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
120 ms |
17348 KB |
Output is correct |
2 |
Correct |
121 ms |
17360 KB |
Output is correct |
3 |
Correct |
120 ms |
17492 KB |
Output is correct |
4 |
Correct |
114 ms |
17492 KB |
Output is correct |
5 |
Correct |
113 ms |
17364 KB |
Output is correct |
6 |
Incorrect |
115 ms |
17356 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |