n = int(input())
l = [[i,0] for i in range(1,n+1)]
for i in range(n-1):
    x = input().split()
    l[int(x[0])-1][1]+=1
    l[int(x[1])-1][1]+=1
if n>1:
    count = -2
else:
    count = 0
for i in range(n):
    if l[i][1]==1:
        count+=1
print(count,end = '')