import sys
from collections import deque

def find_max_k_secure_subnetwork(n, m, k, edges):
    # Szomszédsági lista létrehozása
    adj = [set() for _ in range(n + 1)]
    for u, v in edges:
        adj[u].add(v)
        adj[v].add(u)
    
    # Kezdetben minden csúcs aktív
    active_nodes = set(range(1, n + 1))
    degree = [len(adj[i]) for i in range(n + 1)]
    
    # Sor a törlendő csúcsokhoz
    queue = deque()
    for i in range(1, n + 1):
        if degree[i] < k:
            queue.append(i)
    
    # Iteratív csökkentés
    while queue:
        node = queue.popleft()
        if node not in active_nodes:
            continue
        active_nodes.remove(node)
        for neighbor in adj[node]:
            if neighbor in active_nodes:
                degree[neighbor] -= 1
                if degree[neighbor] < k:
                    queue.append(neighbor)
    
    # Eredmény kiírása
    result = sorted(active_nodes)
    print(len(result))
    if result:
        print(" ".join(map(str, result)))
    
if __name__ == "__main__":
    # Beolvasás
    n, m, k = map(int, sys.stdin.readline().split())
    edges = [tuple(map(int, sys.stdin.readline().split())) for _ in range(m)]
    
    find_max_k_secure_subnetwork(n, m, k, edges)