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 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
int main(void){
    // Your code here!
    char symbol[500010]={};
    int  num[500010];
    scanf("%s",&symbol);
    int i,size;
    for(i=0;500001>i;i++){
        num[i]=-1;
        if(symbol[i]==NULL){
            size = i;
            break;
        }
    }
    int j,k,ct;

    if(symbol[0] == '<'){
        num[0]=0;
        ct=1; k=1;
        while(1){
                if(num[k+1]!=-1||k==size||symbol[k]=='>') break;
                else  num[k] = ct;
                ct++; k++;
            }
    }    
    //printf("%d\n",size);
    if(symbol[size-1] == '>'){
      num[size]=0;
      ct=1;j=size-1;
      while(1){
                if(j==-1||symbol[j]=='<'||num[j]>ct) break;
                else  num[j] = ct;
                ct++; j--;
            }
    } 
    
    for(i=0;size>i;i++){
        
        if(symbol[i]=='>'&&symbol[i+1]=='<'){
            num[i+1]=0;
            j=i; k=i+2; ct=1;
            while(1){
                if(j==-1||symbol[j]=='<'||num[j]>ct) break;
                else  num[j] = ct;
                ct++; j--;
            }
            ct=1;
            while(1){
                if(k>size||symbol[k-1]=='>'||num[k]>ct) break;
                else num[k] = ct;
                ct++; k++;
            }
        }
    }
  
    int sum=0;
    for(i=0;size>=i;i++){
       // if(size>i)  printf("%d%c",num[i],symbol[i]);
        //if(num[i]<0) printf("error\n");
        /*else*/    sum+=num[i];
    }
    //printf("%d\n",num[size]);
    printf("%d\n",sum);
    return 0;
}