Merge Strings Alternately

LeetCode - The World's Leading Online Programming Learning Platform
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.
您将获得两个字符串 word1 和 word2 .通过交替添加字母（从 开始 word1 ）来合并字符串。如果一个字符串比另一个字符串长，请将其他字母附加到合并字符串的末尾。

Return the merged string.
返回合并的字符串。

Example 1: 示例 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: 示例 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: 例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: 约束：

• 1 <= word1.length, word2.length <= 100
• word1 and word2 consist of lowercase English letters.
  word1 由 word2 小写英文字母组成。

class Solution(object):  
    def mergeAlternately(self, word1, word2):  
        """  
        :type word1: str        :type word2: str        :rtype: str  
        """        mergeString = ""  
        i=0  
        j=0  
        while i < len(word1) and j < len(word2):  
            mergeString += word1[i]  
            mergeString += word2[j]  
            i += 1  
            j += 1  
  
        if i < len(word1):  
            mergeString += word1[i:]  
        if j < len(word2):  
            mergeString += word2[j:]  
        return mergeString  
  
    def test(self):  
        word1 = "abc"  
        word2 = "pqr"  
        expected = "apbqcr"  
        actual = self.mergeAlternately(word1, word2)  
        if actual == expected:  
            print("Test passed.")  
        else:  
            print("Test failed. %s != %s" % (actual, expected))  
  
  
  
if __name__ == "__main__":  
    Solution().test()