認證考pE

#include<bits/stdc++.h>
#define debug(x) 0&&(cout<<#x<<':'<<x<<'\n')
#define pb emplace_back
#define REP(i,l,r) for(auto i=(l);i<(r);i++)
#define ff first
#define ss second

using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;
const ll N = 100000,INF = 1e18;

int n,k,d,x,tota,totb,mina,minb,cnt,a[N+1] = {};
vector<int> block;
void solve(){
    cin >> n >> k >> d;
    REP(i,0,n) cin >> a[i];
    sort(a,a+n);
    block.clear();
    cnt = 1;
    REP(i,1,n){
        if(a[i]-a[i-1] > k)block.pb(cnt),cnt = 1;
        else ++cnt;
    }
    block.pb(cnt);
    x = n/d;
    tota = totb = 0;
    debug(x);
    for(auto len:block){
        //ax+b(x+1)=len,
        mina = (x+1-len%(x+1))%(x+1);
        minb = len%x;
        debug(len),debug(mina),debug(minb);
        if(mina >= 0 && minb >= 0)tota += mina, totb += minb;
        else return cout << "NO\n",void();
    }
    if(tota <= d-n%d && totb <= n%d)cout << "YES\n",void();
    else cout << "NO\n",void();
}
signed main(){
    ios::sync_with_stdio(0), cin.tie(0);
    int t;
    cin >> t;
    while(t--)solve();
}