from collections import deque, defaultdict
from intset import IntSet

N, L, B = map(int, input().split())

S, D = map(int, input().split())

rooms = defaultdict(dict)

ALL = IntSet(1, B + 1)
NONE = IntSet()

for i in range(L):
    a, b, x, y = map(int, input().split())
    rooms[a][b] = IntSet(x, y + 1)

ranges = defaultdict(lambda: NONE)
ranges[S] = ALL

q = deque([S])

while q:
    if len(ranges[D]) == B:
        break

    curr = q.pop()

    # if curr == D:
    #     continue

    for neighbor, r in rooms[curr].items():
        old = ranges[neighbor]
        new = ranges[neighbor] | ranges[curr] & r
        if old != new:
            # try:
            #     q.remove(neighbor)
            # except ValueError:
            #     pass
            q.append(neighbor)
        ranges[neighbor] = new

print(len(ranges[D]))