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 Go (1.14.1) (judge verdict: Time Limit Exceeded)

package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	var wtr = bufio.NewWriter(os.Stdout)
	var ans int
	var S string
	fmt.Scan(&S)
	N := len(S) + 1

	a := make([]int, N)
	for i := 0; i < N; i++ {
		j := i
		ar := 0
		for {
			if j < len(S) {
				if S[j] == '>' {
					ar++
				} else {
					break
				}
			} else {
				break
			}
			j++
		}
		j = i - 1
		br := 0
		for {
			if j >= 0 {
				if S[j] == '<' {
					br++
				} else {
					break
				}
			} else {
				break
			}
			j--
		}
		if br > ar {
			ans += br
			a[i] = br
		} else {
			a[i] = ar
			ans += ar
		}

	}
	//fmt.Println(a)
	//fmt.Println()
	fmt.Fprintln(wtr, ans)
	_ = wtr.Flush()
}