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 C# (.NET Core 3.1.201) (judge verdict: Time Limit Exceeded)

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Threading;
using System.IO.Pipes;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string Arr = Console.ReadLine();
            int n = Arr.Length;
            long ans = 0;

            for (int i = 0; i < n + 1; i++) 
            {
                ans += check(Arr, i);
            }
            Console.WriteLine(ans);

        }

        static int checkup(string Arr , int num) 
        {
            if (num == Arr.Length)
            {
                return 0;
            }
            int ret = 0;
            int n = num;
            while (true) 
            {
                if (n == Arr.Length)
                {
                    break;
                }
                if (Arr[n] == '<') 
                {
                    break;
                }else{
                    n++;
                    ret++;
                }
            }
            return ret;
        }
        static int checkdown(string Arr, int num)
        {
            if (num == 0) 
            {
                return 0;
            }
            int ret = 0;
            int n = num;
            while (true)
            {
                if (n == 0)
                {
                    break;
                }
                if (Arr[n-1] == '>')
                {
                    break;
                }
                else
                {
                    n--;
                    ret++;
                }
            }
            return ret;
        }

        static int check(string Arr, int num) 
        {
            return Math.Max(checkup(Arr, num), checkdown(Arr, num));
        }

    }
}