from sys import setrecursionlimit
setrecursionlimit(10**6)

def dfs1(pos):
    ret = 1
    for nxt in G1[pos]:
        ret += dfs1(nxt)
    Dist[pos] = ret
    return ret

N = int(input())
G1 = [[] for _ in range(N)]
G2 = [-1] * N
for _ in range(N-1):
    x,y = map(int,input().split())
    x -= 1
    y -= 1
    G1[x].append(y)
    G2[y] = x
Dist = [-1] * N
dfs1(0)
for i in range(N):
    Dist[i] = [Dist[i], i]
Dist.sort(reverse=True)
Cnt = [0] * N
Flg = [1] * N
for i in range(1,N):
    pos = G2[i]
    Queue = [pos]
    while pos != -1:
        if Cnt[pos] < 2:
            Cnt[pos] += 1
            break
        pos = G2[pos]
        Queue.append(pos)
    if pos == -1:
        for k in Queue:
            G2[k] = -1
        Flg[i] = 0
print(sum(Flg))