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 java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class C {

    void solve(){
        long n = readLong();
        int m = readInt();
        long k = readLong();
        long[] p = new long[m];
        for(int i = 0;i<m;i++){
            p[i] = readLong();
        }

        int ans = 0;
        int del = 0;
        for(int i = 0;i<m;i++){
            ans++;
            int left = i;
            long x = (p[i] - del) / k + ((p[i] - del) % k == 0 ? 0 : 1);
            while(i < m - 1 && ((p[i + 1] - del) / k + ((p[i + 1] - del) % k == 0 ? 0 : 1)) == x){
                i++;
            }
            del += i - left + 1;
        }
        out.print(ans);
    }

    public static void main(String[] args) {
        new C().run();
    }

    void run(){
        init();
        solve();
        out.close();
    }

    BufferedReader in;
    PrintWriter out;

    StringTokenizer tok = new StringTokenizer("");

    void init(){
        in = new BufferedReader(new InputStreamReader(System.in));
        out  = new PrintWriter(System.out);
    }

    String readLine(){
        try{
            return in.readLine();
        }catch(Exception ex){
            throw new RuntimeException(ex);
        }
    }
    String readString(){
        while(!tok.hasMoreTokens()){
            String nextLine = readLine();
            if(nextLine == null) return null;
            tok = new StringTokenizer(nextLine);
        }
        return tok.nextToken();
    }

    int readInt(){
        return Integer.parseInt(readString());
    }

    long readLong(){
        return Long.parseLong(readString());
    }

    double readDouble(){
        return Double.parseDouble(readString());
    }
}
