#include <bits/stdc++.h>
#define ll long long
#define F first
#define S second
#define M 1000000007ll
using namespace std;


bool solve(){
	int n, m;
	if(!(cin >> n >> m)) return false;
	vector<int> a(n);
	for(auto &x : a) {
		cin >> x;
		x--;
	}
	vector<pair<ll, ll>> t;
	bool can = true;
	int mx = -1;
	int v1m = -1, v2m = -1;
	int c1 = 0, c2 = 0;
	for(int i = 0; i < n; ++i){
		mx = max(mx, a[i]);
		if(c1 == 0 || a[i] > v1m) c1++, v1m = a[i];
		else if(c2 == 0 || a[i] > v2m) c2++, v2m = a[i];
		else{
			can = false;
			break;
		}
		if(mx == i){
			t.push_back(pair<ll,ll>(c1, c2));
			c1 = 0, c2 = 0, v1m = -1, v2m = -1;
		}
	}

	if(!can) {
		cout << 0 << '\n';
		return true;
	}

	int A = t[0].F + t[0].S;
	vector<vector<ll>> dp(m+1, vector<ll>(m+1, 0));
	if(t[0].F <= m && t[0].S <= m){
		dp[t[0].F][t[0].S] += 1;
	    dp[t[0].S][t[0].F] += 1;
	}

	for(int i = 1; i < t.size(); ++i){
		for(int j = 0; j <= A; ++j){
			if(t[i].F + j <= m && t[i].S + A - j <= m){
				dp[t[i].F + j][t[i].S + A - j] += dp[j][A - j];
				dp[t[i].F + j][t[i].S + A - j] %= M;
			}
			if(t[i].S + j <= m && t[i].F + A - j <= m){
				dp[t[i].S + j][t[i].F + A - j] += dp[j][A - j];
				dp[t[i].S + j][t[i].F + A - j] %= M;
			}
		}
		A += t[i].F + t[i].S;
	}
	ll ans = 0;
	for(int i = 0; i <= n; ++i){
		if(i <= m && n-i <= m) ans += dp[i][n-i];
		ans %= M;
	}
	cout << ans << '\n';
	return true;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	while(solve());
}