import std.algorithm;
import std.array;
import std.container;
import std.conv;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

T read(T)() { return readln.chomp.to!T; }
T[] reads(T)() { return readln.split.to!(T[]); }
alias readint = read!int;
alias readints = reads!int;

int calc(int c, int k, int[] a) {
    a.sort();
    auto q = DList!int(a);
    int ans = 0;
    while (!q.empty) {
        int time = q.front + k; // 出発時刻
        q.removeFront;
        int passengers = 1; // 乗客
        while (!q.empty && q.front <= time && passengers < c) {
            passengers++;
            q.removeFront;
        }
        ans++;
    }
    return ans;
}

void main() {
    auto nck = readints;
    int n = nck[0], c = nck[1], k = nck[2];
    int[] a;
    for (int i = 0; i < n; i++) a ~= readint;
    writeln(calc(c, k, a));
}
