Description
You are given two strings word1
and word2
. Merge the strings by adding letters in alternating order, starting with word1
. If a string is longer than the other, append the additional letters onto the end of the merged string.
Return the merged string.
Example 1:
Input: word1 = "abc", word2 = "pqr" Output: "apbqcr" Explanation: The merged string will be merged as so: word1: a b c word2: p q r merged: a p b q c r
Example 2:
Input: word1 = "ab", word2 = "pqrs" Output: "apbqrs" Explanation: Notice that as word2 is longer, "rs" is appended to the end. word1: a b word2: p q r s merged: a p b q r s
Example 3:
Input: word1 = "abcd", word2 = "pq" Output: "apbqcd" Explanation: Notice that as word1 is longer, "cd" is appended to the end. word1: a b c d word2: p q merged: a p b q c d
Constraints:
1 <= word1.length, word2.length <= 100
word1
andword2
consist of lowercase English letters.
Solution
Python3
class Solution:
def mergeAlternately(self, word1: str, word2: str) -> str:
N, M = len(word1), len(word2)
res = []
i = j = 0
while i < N or j < M:
if i < N:
res.append(word1[i])
i += 1
if j < M:
res.append(word2[j])
j += 1
return "".join(res)