Description
https://leetcode.com/problems/keyboard-row/
Given an array of strings words, return the words that can be typed using letters of the alphabet on only one row of American keyboard like the image below.
In the American keyboard:
- the first row consists of the characters
"qwertyuiop", - the second row consists of the characters
"asdfghjkl", and - the third row consists of the characters
"zxcvbnm".
Example 1:
Input: words = ["Hello","Alaska","Dad","Peace"] Output: ["Alaska","Dad"]
Example 2:
Input: words = ["omk"] Output: []
Example 3:
Input: words = ["adsdf","sfd"] Output: ["adsdf","sfd"]
Constraints:
1 <= words.length <= 201 <= words[i].length <= 100words[i]consists of English letters (both lowercase and uppercase).
Explanation
Check if characters in words are in the same keyboard row.
Python Solution
class Solution:
def findWords(self, words: List[str]) -> List[str]:
results = []
row1 = ["q", "w", "e", "r", "t", "y", "u", "i", "o", "p"]
row2 = ["a", "s", "d", "f", "g", "h", "j", "k", "l"]
row3 = ["z", "x", "c", "v", "b", "n", "m"]
for word in words:
is_same = True
prev_row = 0
for c in word.lower():
row = None
if c in row1:
row = 1
elif c in row2:
row = 2
elif c in row3:
row = 3
if prev_row != 0 and row != prev_row:
is_same = False
break
prev_row = row
if is_same:
results.append(word)
return results
- Time Complexity: O(N).
- Space Complexity: O(N).