// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
std::ifstream terminal("/dev/tty");
#define PP cerr<<"\033[1;30mpause...\e[0m",terminal.ignore();
#else
#define debug(x...)
#define Debug(x...)
#define PP
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define VI vector<int>
#define VII vector<vector<int>>
#define VIII vector<vector<vector<int>>>
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x), __VA_ARGS__})
#define cmax(x,...) x=max({(x), __VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define NaN (int)(0x8b88e1d0595d51d1)
#define double long double
#define int long long
#define uint unsigned long long
#define MAXN 200010
#define P 1000000007

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    int n, ub; cin >> n >> ub;
    vector<int> a(n);
    rep(i, 0, n) cin >> a[i];
    vector<vector<int>> dp(n, vector<int>(ub+1, 0));
    if (a[0]) dp[0][a[0]] = 1;
    else fill(dp[0].begin()+1, dp[0].end(), 1);
    rep(i, 1, n) {
        if (a[i]) {
            for (int k = a[i]-1; k <= a[i]+1; ++k) {
                if (k >= 1 && k <= ub) {
                    dp[i][a[i]] += dp[i-1][k];
                    dp[i][a[i]] %= P;
                }
            }
        }
        else {
            rep(j, 1, ub+1) {
                for (int k = j-1; k <= j+1; ++k) {
                    if (k >= 1 && k <= ub) {
                        dp[i][j] += dp[i-1][k];
                        dp[i][j] %= P;
                    }
                }
            }
        }
    }
    int ans;
    if (a[n-1]) ans = dp[n-1][a[n-1]];
    else ans = accumulate(dp[n-1].begin()+1, dp[n-1].end(), 0LL) % P;
    cout << ans << endl;

    return 0;
}