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.

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.

Constraints

• $2 \leq N \leq 5 \times 10^5$
• S is a string of length N-1 consisting of < and >.

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

见题面 Input 部分

见题面 Output 部分