My good friend Guruji once submitting his code on forum mistakenly forgot to check language option. His code got pasted in general editor. Due to this many portion of his code got changed. One funny thing which happened was that sub-string "<3" got changed into a heart.
Your job is simple, count the number of "<3"(quotes for clarity) in a given string.

|s| deontes the length of string

Constraint:
0 < |s| < 100 

Input:
It will consist of one line, containing the string

Output: 
Consist of one line containing an integer.

Sample Input:

abcd<3abc<3ab<3ab

Sample Output:

3

SAMPLE INPUT
abcd<3abc<3ab<3ab

SAMPLE OUTPUT
3
'''
# Read input from stdin and provide input before running code

name = raw_input('What is your name?\n')
print 'Hi, %s.' % name
'''
s=raw_input()
l=len(s)
c=0
for i in range(0,l-1):
	if s[i] == '<':
		if s[i+1] == '3':
			c=c+1
print c