10 5 5
2 3 4 5 6
 1 1 1
1
 1000000000000000000 10 68
9818112234872670 233245257111863071 266483628625876079 375103213040049805 431982380866113633 489732004669478331 501030096787260719 541800997319766183 551892546260532408 696178619227890200
 1000000000000000000 2 1
1 1000000000000000000
 33 32 1
1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
 101 55 10
1 3 5 7 8 9 10 16 18 21 22 23 24 25 27 30 32 35 36 37 38 39 40 43 45 47 49 50 51 52 54 57 59 61 64 66 67 68 69 70 71 72 73 80 83 86 87 88 89 90 91 92 96 97 98
 1000000000000000000 5 1000
1 1000000000 1000000000000 1000000000000000 1000000000000001
 15 15 15
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
 21 21 20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
 45 43 2
1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
 107 20 13
5 9 20 25 26 30 37 45 51 58 62 73 82 87 89 90 99 101 104 106
 3 2 1
1 2
 1000000000 2 1000000000
1 1000000000
 11 7 3
2 3 4 5 6 7 11
 13 9 4
1 2 3 6 7 8 11 12 13
 1000000000000000000 2 1000000000
102306300054748096 267367244641009859
 16 7 5
2 3 4 5 6 15 16
 35 35 1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
 1000000000000000000 20 365
31881893160049984 103938857870698567 103962228223609431 140762820261865064 175962215264653912 239086305245565642 354522451098745823 383839975876242372 443471287955807705 478923027151493682 511195154588214957 619570919279066139 677571312513476877 705864797651447277 789633853044745934 867300890280086078 883297431113041450 891736036124527038 937306858250803630 990892290394455512

2
 1
 10
 2
 32
 15
 4
 1
 2
 35
 9
 2
 1
 4
 4
 2
 4
 35
 20

/***
 *    ██████╗=====███████╗====███████╗====██████╗=
 *    ██╔══██╗====██╔════╝====██╔════╝====██╔══██╗
 *    ██║==██║====█████╗======█████╗======██████╔╝
 *    ██║==██║====██╔══╝======██╔══╝======██╔═══╝=
 *    ██████╔╝====███████╗====███████╗====██║=====
 *    ╚═════╝=====╚══════╝====╚══════╝====╚═╝=====
 *    ============================================
 */

import sun.nio.cs.KOI8_U;

import java.io.*;
import java.util.*;
import java.math.*;
import java.lang.*;

public class AA implements Runnable {


    public void run() {
        InputReader sc = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int i=0,j=0,k=0;
        int t=0;
        //t=sc.nextInt();
        for(int testcase = 0; testcase < t; testcase++)
        {

        }

        long n=sc.nextInt();
        int m=sc.nextInt();
        int pagessize=sc.nextInt()+1;
        int count=0;
        int minus=0;
        int arr[]=sa(m,sc);
        i=0;
        while (i<m)
        {
            //out.println("1");
            int temp=(arr[i]-minus)/pagessize;
            int tempminus=minus;
            minus++;
            i++;
            while (i<m&&(arr[i]-tempminus)/pagessize==temp)
            {
                //out.println("2");
                minus++;
                i++;
            }
            //out.println(i+"  //");
            count++;
        }
        out.println(count);


//================================================================================================================================
        out.flush();
        out.close();
    }


//================================================================================================================================
public static int[] sa(int n,InputReader sc)
{
    int arr[]=new int[n];
    for (int i=0;i<n;i++)
        arr[i]=sc.nextInt();
    return arr;
}

    public static long gcd(long a,long b){
        return (a%b==0l)?b:gcd(b,a%b);
    }
    private static long lcm(long a, long b)
    {
        return a * (b / gcd(a, b));
    }
    public int egcd(int a, int b) {
        if (a == 0)
            return b;

        while (b != 0) {
            if (a > b)
                a = a - b;
            else
                b = b - a;
        }

        return a;
    }



    public int countChar(String str, char c)
    {
        int count = 0;
        for(int i=0; i < str.length(); i++)
        {    if(str.charAt(i) == c)
            count++;
        }
        return count;
    }
    static int binSearch(Integer[] arr, int number){
        int left=0,right=arr.length-1,mid=(left+right)/2,ind=0;
        while(left<=right){
            if(arr[mid]<=number){
                ind=mid+1;
                left=mid+1;
            }
            else
                right=mid-1;
            mid=(left+right)/2;
        }
        return ind;
    }
    static int binSearch(int[] arr, int number){
        int left=0,right=arr.length-1,mid=(left+right)/2,ind=0;
        while(left<=right){
            if(arr[mid]<=number){
                ind=mid+1;
                left=mid+1;
            }
            else
                right=mid-1;
            mid=(left+right)/2;
        }
        return ind;
    }
    static class Pair
    {
        int a,b;
        Pair(int aa,int bb)
        {
            a=aa;
            b=bb;
        }
        String get()
        {
            return a+" "+b;
        }
        String getrev()
        {
            return b+" "+a;
        }
    }

    static boolean isPrime(long n) {
        if(n < 2) return false;
        if(n == 2 || n == 3) return true;
        if(n%2 == 0 || n%3 == 0) return false;
        long sqrtN = (long)Math.sqrt(n)+1;
        for(long i = 6L; i <= sqrtN; i += 6) {
            if(n%(i-1) == 0 || n%(i+1) == 0) return false;
        }
        return true;
    }
    static long factorial(long n)
    {
        if (n == 0)
            return 1;
        return n*factorial(n-1);
    }
//================================================================================================================================

    static class InputReader
    {
        BufferedReader br;
        StringTokenizer st;

        public InputReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException  e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }

    public static void main(String args[]) throws Exception {
        new Thread(null, new AA(),"Main",1<<27).start();
    }
}
