821. Shortest Distance to a Character - LeetCode Solution

class Solution:
    from math import fabs
    def shortestToChar(self, s: str, c: str) -> List[int]:
        

        pos = []
        for i in range(len(s)):
            if s[i] == c:
                pos.append(i)

        first = pos[0]
        second = pos[0]
        count = 0
        ans = []
        for i in range(len(s)):
            a = int(fabs(i - first))
            b = int(fabs(second - i))


            if a == 0 or b == 0:
                first = second
                if count<len(pos)-1:
                    count+=1
                    second = pos[count]

            ans.append(min(a, b))

        return ans