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 scanner = new Scanner(System.in);
        String s = scanner.next();
        int n = s.length() + 1;

        int[] lt = new int[n];
        int[] gt = new int[n];

        for (int i = 0; i < n - 1; i++) {
            if (s.charAt(i) == '<') {
                lt[i + 1] = lt[i] + 1;
            }
        }
        for (int i = n - 2; i >= 0; i--) {
            if (s.charAt(i) == '>') {
                gt[i] = gt[i + 1] + 1;
            }
        }
        long sum = 0;
        for (int i = 0; i < n; i++) {
            sum += Math.max(lt[i], gt[i]);
        }
        System.out.println(sum);
    }

}