# AOJ 2831: Check answers

# Python3 2018.7.12 bal4u



n = int(eval(input()))

if n == 0: print((0))

else:

	s = eval(input())

	ans = 1

	for i in range(1, len(s)):

		if s[i-1] == 'x' and s[i] == 'x': break

		ans += 1

	print(ans)



# AOJ 2831: Check answers

# Python3 2018.7.12 bal4u



n = int(eval(input()))

if n == 0: print((0))

else:

	s = eval(input())

	ans = 1; pre = s[0]

	for t in s[1:]:

		if pre == 'x' and t == 'x': break

		pre = t; ans += 1

	print(ans)



# AOJ 2831: Check answers
# Python3 2018.7.12 bal4u
n = int(eval(input()))
if n == 0:
    print((0))
else:
    s = eval(input())
    ans = 1
    for i in range(1, len(s)):
        if s[i - 1] == "x" and s[i] == "x":
            break
        ans += 1
    print(ans)

# AOJ 2831: Check answers
# Python3 2018.7.12 bal4u
n = int(eval(input()))
if n == 0:
    print((0))
else:
    s = eval(input())
    ans = 1
    pre = s[0]
    for t in s[1:]:
        if pre == "x" and t == "x":
            break
        pre = t
        ans += 1
    print(ans)

-    for i in range(1, len(s)): -        if s[i - 1] == "x" and s[i] == "x": +    pre = s[0] +    for t in s[1:]: +        if pre == "x" and t == "x": +        pre = t