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: Accepted)

use proconio::input;

#[allow(unused_imports)]
use proconio::marker::{Bytes, Chars, Usize1};
#[allow(unused_imports)]
use std::cmp::*;
#[allow(unused_imports)]
use std::collections::*;
#[allow(unused_imports)]
use std::ops::*;
#[derive(Clone, Debug, Default)]
struct Struct;

//#[proconio::fastout]
fn main() {
    input! {
        mut s:Chars,
    }

    let len = s.len() + 1;
    let mut lmin = vec![0u64;len];
    let mut rmin = vec![0u64;len];

    // 左から見たときの下限
    lmin[0] = 0;
    for i in 1..len {
        if s[i - 1] == '<' {
            lmin[i] = lmin[i - 1] + 1;
        } else {
            lmin[i] = 0;
        }
    }

    // 右から見たときの下限
    s.reverse();
    rmin[0] = 0;
    for i in 1..len {
        if s[i - 1] == '>' {
            rmin[i] = rmin[i - 1] + 1;
        } else {
            rmin[i] = 0;
        }
    }
    s.reverse();
    rmin.reverse();


    let mut ans = 0;
    for i in 0..len {
        ans += max(lmin[i],rmin[i]);
    }
    println!("{}", ans);
}