// #include <bits/stdc++.h>
#include <iostream>
#include <vector>
#include <string>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> PP;
// #define MOD 1000000007
#define MOD 998244353
#define INF 2305843009213693951ll
#define PI 3.141592653589
#define setdouble setprecision
#define REP(i,n) for(ll i=0;i<(n);++i)
#define OREP(i,n) for(ll i=1;i<=(n);++i)
#define RREP(i,n) for(ll i=(n)-1;i>=0;--i)
#define ORREP(i,n) for(ll i=(n);i>=1;--i)
#define rep(i,a,b) for(ll i=(a);i<=(b);++i)
#define ALL(v) (v).begin(), (v).end()
#define chmin(k,m) k = min(k,m)
#define chmax(k,m) k = max(k,m)
#define GOODBYE do { cout << "-1" << endl; return 0; } while (false)
#define MM <<" "<<
#define Endl endl

int main(void){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    
    ll N,M,T;
    cin >> N >> M >> T;
    vector<ll> A(N,0);
    REP(i,M){
        ll a;
        cin >> a;
        a--;
        A[a]++;
    }

    // ok 分で全部焼けるか
    ll ok = -1, ng = 0, mid;
    REP(i,N){
        ok = max(ok,A[i]);
    }

    while(abs(ok-ng)>1){
        mid = (ok+ng)/2;

        ll r = 0, f = 0;
        REP(i,N){
            // 受け入れ余裕あり
            if(A[i]<=mid){
                f += (mid-A[i])/T;
            }else{
            // 放出
                r += (A[i]-mid);
            }
        }

        if(r<=f){
            ok = mid;
        }else{
            ng = mid;
        }

    }

    cout << ok << endl;

    
    return 0;
    
}