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

/*	PREYANSH RASTOGI	*/

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file 
#include <ext/pb_ds/tree_policy.hpp> 
#include <functional> // for less 
using namespace __gnu_pbds; 
using namespace std ;

typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set; 

#define IOS ios_base::sync_with_stdio(false) ;	cin.tie(0);	cout.tie(0);
#define int long long
#define vl vector<int>
#define vvl vector< vector<int> >
#define pll pair<int,int>
#define maxheap priority_queue<int>
#define minheap priority_queue<int,vector<int> ,greater<int>>
#define INF numeric_limits<int>::max()
#define gcd(a,b) __gcd(a,b)
#define pb push_back 
#define mp make_pair
#define mapll unordered_map<int,int>
#define ld long double
#define ff first
#define ss second
#define endl "\n"

const int mod = 1e9 + 7  ; 
const int N5 = 1e5 +9;
const int N6 = 1e6 +9; 

int pow (int a , unsigned int b ,int m ) {
	int ans =  1 ; a=a%m;
	while (b > 0) {
		if ( b & 1) ans = (ans*a)%m ; 
		a = (a*a)%m ; b = b>>1;
	}
	return ans;
}

int modInverse(int a , int m ) { 
	return pow(a,m-2,m)%m ; 
}

void init( ) {

}

signed main() {

	IOS ;

	
    #ifndef ONLINE_JUDGE

    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    freopen("error.txt", "w", stderr);

    #endif

    clock_t t1, t2;
	t1 = clock();

	int n,m,k ;
	cin >> n >>m >> k ;

	int arr[m] ; 
	for (int i = 0 ; i < m ; i++) {
		cin >> arr[i] ;
	}

	int ans = 0 ;

	int start = 1 ; 
	int rem = 0 ;
	for (int i = 0 ; i < m ; i++) {
		// cout << arr[i] << " " << ans  << " " << start << endl ; ;
		if (arr[i] > start + k - 1) {
			if (rem > 0) {
				
				start += rem ;
				if (arr[i] > start + k - 1) 
					start += (arr[i] - start)*k ;
				i-- ;

				rem = 0;	
			} 
			else {
				start += k ;
			}
		}
		else {
			if (rem == 0)
				ans ++ ;
			rem ++ ;
		}
	}

	cout << ans << endl ;

	t2 = clock(); cerr << "time taken: " << (t2-t1)/(ld)CLOCKS_PER_SEC;


    return  0 ; 
    
}







