# Sprint 1 Challenge Problems
## [Shortest Distance To a Character](https://leetcode.com/problems/shortest-distance-to-a-character/)

class Solution:
    """
    Plan
    Keep track of the occurences of the character and use two pointers to determine whether which index is closer from the right or left
    Runtime: O(length of s)
    Space: O(length of s)
    """
    def shortestToChar(self, s: str, c: str) -> List[int]:
        indices = []
        res = []
        for i, char in enumerate(s):
            if char == c:
                indices.append(i)
        pointerA = 0
        pointerB = min(len(indices) - 1, 1)
        for i, char in enumerate(s):
            distFromA = abs(i - indices[pointerA])
            distFromB = abs(i - indices[pointerB])
            res.append(min(distFromA, distFromB))
            if distFromB < distFromA:
                pointerA = pointerB if pointerB + 1 == len(indices) else pointerB + 1
            else:
                pointerB = pointerA if pointerA + 1 == len(indices) else pointerA + 1
        return res

## [Num Lines to Write String](https://leetcode.com/problems/number-of-lines-to-write-string/)

class Solution:
    """
    Plan
    Just manually count the number of lines needed and the width of the current line
    Runtime: O(length of s)
    Space: O(1)
    """
    def numberOfLines(self, widths: List[int], s: str) -> List[int]:
        numLines = 1
        currLineCharCount = 0
        for char in s:
            charWidth = widths[ord(char) - ord('a')]
            if currLineCharCount + charWidth > 100:
                numLines += 1
                currLineCharCount = charWidth
            else:
                currLineCharCount += charWidth
        return [numLines, currLineCharCount]

## [Are Two String Arrays Equivalent](https://leetcode.com/problems/check-if-two-string-arrays-are-equivalent/)

"""
Plan
Concatenate all strings from both words and just use the == operator
Runtime (n + m)
Space O(n + m) where n = length of word1, m = length of word2
"""

class Solution:
    def arrayStringsAreEqual(self, word1: List[str], word2: List[str]) -> bool:
        return "".join(word1) == "".join(word2)