#include <bits/stdc++.h>
#define MOD 9901
using namespace std;

ifstream ci("pod.in");
ofstream cou("pod.out");

int n,m,k;
short dp[100000005];
bool eg[100000005];
void citire(){
    ci>>n>>m>>k;
    int p;
    for(int i=1;i<=m;i++){
        ci>>p;
        eg[p]=1;
    }
}

void rez(){
    dp[0]=1;
    int s=0;
    for(int i=1;i<=n;i++){
        s=0;
        for(int j=i-1;j>=max(0,i-k);j--){
            s+=dp[j];
        }
        if(eg[i]==0){
            dp[i]=s;
        }else{
            dp[i]=0;//inutil
        }
    }
    cou<<dp[n];
}

int main()
{
    citire();
    rez();
    return 0;
}