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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String s = in.nextLine();
        long[] array = new long[s.length() + 1];
        for (int j = 1; j <= s.length(); j++) {
            if (s.charAt(j - 1) == '<') {
                array[j] = array[j - 1] + 1L;
            }
        }
        long answer = array[s.length()];
        for (int j = s.length() - 1; j >= 0; j--) {
            if (s.charAt(j) == '>') {
                array[j] = Math.max(array[j], array[j + 1] + 1);
            }
            answer += array[j];
        }
        System.out.println(answer);
    }
}