array_description.cpp

//
// Created by innav_z3e3dq9 on 2/5/2025.
//

#include <bits/stdc++.h>
using namespace std;

int main() {
    int mod = 1e9+7;
    int n, m;
    cin >> n >> m;
    vector dp(n,vector<int>(m+1));
    int x0;
    cin >> x0;
    if (x0 == 0) {
        fill(dp[0].begin(), dp[0].end(), 1);
    } else {
        dp[0][x0] = 1;
    }
    for (int i = 1; i < n; i++) {
        int x;
        cin >> x;
        if (x == 0) {
            for (int j = 1; j <= m; j++) {
                for (int k : {j-1,j,j+1}) {
                    if (k >= 1 && k <= m) {
                        (dp[i][j] += dp[i-1][k]) %= mod;
                    }
                }
            }
        } else {
            for (int k : {x-1, x, x+1}) {
                if (k >= 1 && k <= m) {
                    (dp[i][x] += dp[i-1][k]) %= mod;
                }
            }
        }
    }
    int ans = 0;
    for (int j = 1; j <= m; j++) {
        (ans += dp[n-1][j]) %= mod;
    }
    cout << ans << endl;
}