#include<bits/stdc++.h>
#define int long long
using namespace std;
int a[1000001], fact[1000001], inv[1000001], color[1000001];
const int mod = 1e6+3;
int power(int a, int b)
{
if(b == 0) return 1;
int ans = power(a, b/2);
ans = (ans * ans)%mod;
if(b%2 == 1) ans = (ans * a)%mod;
return ans;
}
int C(int k, int n)
{
if(k > n || k < 0) return 0;
return (fact[n] * ((inv[k] * inv[n-k])%mod))%mod;
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, k;
cin>>n>>k;
fact[0] = inv[0] = 1;
for(int i = 1; i <= n; i++) fact[i] = (fact[i-1] * i)%mod;
inv[n] = power(fact[n], mod-2);
for(int i = n-1; i >= 1; i--) inv[i] = (inv[i+1] * (i+1))%mod;
for(int i = 1; i <= n-k+1; i++) cin>>a[i];
for(int i = 1; i <= n; i++) color[i] = 2;
for(int i = n-k; i >= 1; i--){
if(abs(a[i] - a[i+1]) > 1){cout<<0; return 0;}
if(a[i] == a[i+1]) color[i] = color[i+k];
else if(a[i] > a[i+1]){
if(color[i+k] == 1){cout<<0; return 0;}
color[i] = 1;
}
else{
if(color[i+k] == 0){cout<<0; return 0;}
color[i] = 0;
}
}
/*for(int i = 1; i <= n; i++) cout<<color[i]<<" ";
cout<<'\n';*/
int re = 0;
for(int i = 1; i <= k; i++){a[1] -= (color[i] == 1); re += (color[i] == 2);}
cout<<C(a[1], re);
}
