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++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
int main()
{
    string s;
    cin>>s;
    int n=s.size();
    vector<int> left(n+1);
    vector<int> right(n+1);
    int prev=0;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='<')
        {
            left[i+1]=prev+1;
            prev++;
        }
        else
        {
            left[i+1]=0;
            prev=0;
        }
    }
    prev=0;
    for(int i=n-1;i>=0;i--)
    {
        if(s[i]=='>')
        {
            right[i]=prev+1;
            prev++;
        }
        else
        {
            right[i]=0;
            prev=0;
        }
    }
    int ans=0;
    for(int i=0;i<=n;i++)
    {
        ans+=max(left[i],right[i]);
    }
    cout<<ans;
    return 0;
}