#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <set>
using namespace std;
const int N = 1e5 + 5;

vector<int> G[N];
set<int> ID;
int n, d, k;

bool isHot(int id)
{
    sort(G[id].begin(), G[id].end());
    for (int i = 0; i + k - 1< G[id].size(); ++i)
    {
        if (G[id][i+k-1] - G[id][i] < d)
            return true;
    }
    return false;
}

int main()
{
    scanf("%d %d %d", &n, &d, &k);
    for (int i = 0; i < n; ++i)
    {
        int ts, id;
        scanf("%d %d", &ts, &id);
        G[id].push_back(ts);
        ID.insert(id);
    }

    set<int>::iterator it;
    for (it = ID.begin(); it != ID.end(); ++it)
    {
        int id = *it;
        if (isHot(id))
            printf("%d\n", id);
    }
    return 0;
}