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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;
int main()
{
	string s;
	cin>>s;
	int l = s.length();
	long long res = 0,i = 0;
	while(i<l)
	{
		int p = 0, q = 0;
		while(s[i]=='<' && i<l)
		{
			i++;
			p++;
		}
		while(s[i]=='>' && i<l)
		{
			i++;
			q++;
		}
		if(p<q)
			swap(p,q);
		p = p*(p+1)/2;
		q = q*(q-1)/2;
		res+= p + q;
	}
	cout<<res<<'\n';
}