Tietoverkko

n = int(input())
m = {}
c=0
v = []
counter = 0
for i in range(1,1+n):
	m[i] = []
for i in range(n):
	a,b = input().split()
	a = int(a)
	b = int(b)
	m[a].append(b)
	m[b].append(a)
 
for i in range(0,100):
	for i,j in m.items():
		counter = 0	
		if len(j) == 1:
			v.append(i)
		else:
			for x in range(len(j)):
				if j[x-counter] in v:
					del j[x-counter]
					counter += 1
					#print(j[x-counter])
				
for i in range(1,1+len(m)):
	if len(m[i]) == 1:
		c+=1
print(c)

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED