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 Rust (1.42.0) (judge verdict: Wrong Answer)

use proconio::input;
use proconio::marker::Chars;

fn main() {
    input! {
        s: Chars
    }

    let n = s.len()+1;

    let mut left = Vec::new();
    left.push(0);
    let mut num = 0;
    for i in 0..n-1 {
        if s[i] == '<' {
            num += 1;
        } else {
            num = 0;
        }
        left.push(num);
    }

    let mut right = vec![0; n];
    let mut num = 0;
    for i in (0..n-1).rev() {
        if s[i] == '>' {
            num += 1;
        } else {
            num = 0;
        }
        right[i] = num;
    }

    let ans = {
        let mut ans = 0;
        for i in 0..n {
            ans += left[i].max(right[i]);
        }
        ans
    };


    println!("{}",ans)
}