Problem:
Score : 300 points

Problem Statement

Given is a string S of length N-1.
Each character in S is < or >.

A sequence of N non-negative integers, a_1,a_2,\cdots,a_N, is said to be good when the following condition is satisfied for all i (1 \leq i \leq N-1):

If S_i= <: a_i<a_{i+1}

If S_i= >: a_i>a_{i+1}

Find the minimum possible sum of the elements of a good sequence of N non-negative integers.

Constraints

2 \leq N \leq 5 \times 10^5

S is a string of length N-1 consisting of < and >.

Input

Input is given from Standard Input in the following format:

S

Output

Find the minimum possible sum of the elements of a good sequence of N non-negative integers.

Sample Input 1

<>>

Sample Output 1

3

a=(0,2,1,0) is a good sequence whose sum is 3.
There is no good sequence whose sum is less than 3.

Sample Input 2

<>>><<><<<<<>>><

Sample Output 2

28

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

S = input()
s = len(S)
ans_list = list()

for i in range(s):
  n = i
  k1 = 0
  k = 0
  j = -1
  if S[i] == ">" and S[i-1] == "<":
    while 0 < n and S[i -1] == S[n -1]:
      k += 1
      n -= 1
    n = i
    while n <= s - 1 and S[i] == S[n]:
      k1 += 1
      n += 1
    k = max(k,k1)
      
  elif S[i] == ">":
    while n <= s - 1 and S[i] == S[n]:
      k += 1
      n += 1
  else:
    while 0 < n and S[i] == S[n]:
      j += 1
      n -= 1
  ans_list.append(max(k,j))
if S[-1] == ">":
  print(sum(ans_list))
elif S[-1] == "<" and S[-1] == "<":
  print(sum(ans_list) +ans_list[-1] +1)
else:
  print(sum(ans_list) +1)