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

#include <bits/stdc++.h>
using namespace std;
long long int bg = 998244353;
long long int gcd(long long int a, long long int b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
long long int power(long long int x, long long int y, long long int p) {
  if (x == 0) return 0;
  if (y == 0) return 1;
  long long int s = y / 2;
  long long int f = power(x, s, p) % p;
  if (y % 2 == 0)
    return (f * f) % p;
  else
    return (((f * f) % p) * x % p) % p;
}
void build1(long long int node, long long int seg[], long long int arr[],
            long long int start, long long int end) {
  if (start == end) {
    seg[node] = arr[start];
    return;
  }
  long long int mid = (start + end) / 2;
  build1(2 * node, seg, arr, start, mid);
  build1(2 * node + 1, seg, arr, mid + 1, end);
  seg[node] = seg[2 * node] + seg[2 * node + 1];
}
long long int query1(long long int node, long long int seg[],
                     long long int arr[], long long int start,
                     long long int end, long long int l, long long int r) {
  long long int mid = (start + end) / 2;
  if (r < start || l > end)
    return 0;
  else if (l <= start && r >= end)
    return seg[node];
  else
    return query1(2 * node, seg, arr, start, mid, l, r) +
           query1(2 * node + 1, seg, arr, mid + 1, end, l, r);
}
long long int page(long long int f, long long int rem, long long int k) {
  long long int x, n = f - rem;
  if (n % k == 0)
    x = n / k;
  else
    x = n / k + 1;
  return x;
}
int main() {
  long long int i, j, n, m, k, pos = 0, rem = 0, mov = 0;
  cin >> n >> m >> k;
  long long int arr[m];
  for (i = 0; i < m; i++) cin >> arr[i];
  while (pos < m) {
    for (j = pos; (page(arr[pos], rem, k) == page(arr[j], rem, k) && j < m);
         j++) {
    }
    pos = j;
    rem = j;
    mov++;
  }
  cout << mov << '\n';
  return 0;
}
