#include <bits/stdc++.h>

using namespace std;

const int N = 1e6 + 5, P = 1e6 + 3;

int a[N];

int C(int x, int y) {
    if (x < 0 || y < 0 || x < y) return 0;
    int up = 1, down = 1;
    for (int i = 1; i <= y; ++i) {
        up = 1ll * up * (x - i + 1) % P;
        down = 1ll * down * i % P;
    }
    auto inv = [&](auto &&self, int a, int b) -> int {
        return (a == 1 ? 1 : b - 1ll * self(self, b % a, a) * b / a);
    };
    return 1ll * up * inv(inv, down, P) % P;
}

signed main() {
    int n, m; scanf("%d%d", &n, &m);
    for (int i = 1; i <= n - m + 1; ++i) scanf("%d", &a[i]);
    int t[4] = {0, 0, 0, 0};
    for (int i = 1; i <= m; ++i) {
        int o = 3;
        long long s1 = 0, s2 = 0;
        for (int j = i + 1; j <= n - m + 1; ++j) {
            s1 += a[j - 1], s2 += a[j];
            if (abs(s1 - s2) >= 2) o = 0;
            if (s1 > s2) o &= 2;
            if (s1 < s2) o &= 1;
        }
        if (!o) return 0 & puts("0");
        ++t[o];
    }
    printf("%d\n", C(t[3], a[1] - t[2]));
    return 0;
}