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 stdIn = new Scanner(System.in);


		String[] s = stdIn.next().split("");

		int[] a = new int[s.length+1];

		for(int i = 0; i < s.length; i++) {
			if(s[i].equals("<")) {
				a[i+1] = a[i]+1;
			}
		}

		for(int i = s.length-1; i>=0; i--) {
			if(s[i].equals(">")){
				a[i] = Math.max(a[i+1]+1, a[i]);
			}
		}

		long sum = 0;
		for(int i = 0; i < a.length; i++) {
			sum += a[i];
		}

		System.out.println(sum);
	}

}