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 (1.15.1) (judge verdict: Accepted)

#[allow(unused_macros)]
macro_rules! input {
    ( $($t:ty),* ) => {{
        let mut s = String::new();
        std::io::stdin().read_line(&mut s);
        let mut splits = s.trim().split_whitespace();
        ($( { splits.next().unwrap().parse::<$t>().unwrap() },)*)
    }}
}

#[allow(unused_must_use)]
#[allow(unused_variables)]
fn solve() {
    let (s,) = input!(String);

    let mut lt = Vec::with_capacity(s.len() - 1);
    let mut gt = Vec::with_capacity(s.len() - 1);

    lt.push(0);
    gt.push(0);

    let mut count = 0;
    for c in s.chars() {
        match c {
            '<' => count += 1,
            '>' => count = 0,
            _ => {},
        }
        
        lt.push(count);
    }

    let mut count = 0;
    for c in s.chars().rev() {
        match c {
            '>' => count += 1,
            '<' => count = 0,
            _ => {},
        }
        gt.push(count);
    }

    let minimum_vec = lt.iter().zip(gt.iter().rev()).map(|(a, b)| std::cmp::max(a, b));
    let total: u64 = minimum_vec.sum();
    
    println!("{}", total);
}

fn main() {
    solve();
}