#include <fstream>
#include <algorithm>

using namespace std;

ifstream fin("zombie.in");
ofstream fout("zombie.out");

int n,k,cost,sol;
int start,cur=0;

int main()
{
    fin>>k>>n>>cost;
    fin>>start;
    cur=1;
    for(int i=2;i<=n;i++)
    {
        int a;
        fin>>a;
        if(a-start>k)
        {
            sol+=min(cur,cost);
            start=a;
            cur=0;
        }
        cur++;
    }
    sol+=min(cur,cost);
    fout<<sol;
    return 0;
}