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.*;
import java.util.*;

public class C {

	void run() {
		long n = in.nextLong();
		int m = in.nextInt();
		long k = in.nextLong();

		long curr = -1;
		long prev_page = -1, curr_page = -1;
		long n_rem = 0;
		int n_group = 0;
		int n_op = 0;

		int i;
		
		for(i=0;i<m;i++){
			curr = in.nextLong() - n_rem - 1;
			curr_page = curr / k;
			if((i==0) || curr_page == prev_page){
				n_group++;
			}else{
				// do op
				n_op++;
				n_rem += n_group;
				curr_page = (curr - n_group) / k;
				n_group = 1;
			}
			prev_page = curr_page;
		}
		// close last group
		n_op++;
		out.println(n_op);

	}
	
	static MyScanner in;
	static PrintWriter out;

	public static void main(String[] args) throws IOException {
		boolean stdStream = true;
		if(stdStream){
			in = new MyScanner();
			out = new PrintWriter(System.out);
		}else{
			String fileName = C.class.getSimpleName();
			int n_test = 2;			
			String inputFileName = fileName + String.format(".%02d", n_test) + ".inp";
			String outputFileName = fileName + String.format(".%02d", n_test) + ".out";
			in = new MyScanner(new BufferedReader(new FileReader(inputFileName)));
			out = new PrintWriter(outputFileName);
		}
			
		new C().run();

		in.close();
		out.close();
	}

	static class MyScanner {
		BufferedReader br;
		StringTokenizer st;

        MyScanner(){
            this.br = new BufferedReader(new InputStreamReader(System.in));
        }

		MyScanner(BufferedReader br) {
			this.br = br;
        }

        void close() throws IOException {
            br.close();
        }
        
		void findToken() {
			while (st == null || !st.hasMoreTokens()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
		}
		
		String next() {
			findToken();
			return st.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
		
		double nextDouble() {
			return Double.parseDouble(next());
		}
	}
}