Given two strings s and t which consist of only lowercase letters.
String t is generated by random shuffling string s and then add one more letter at a random position.
Find the letter that was added in t.
Example:
Input:
s = "abcd"
t = "abcde"
Output:
e
Explanation:
'e' is the letter that was added.
这道题的意思是 给两个字符串,第二个字符串是第一个的乱序后再随机插入一个字母在随机的位置
要我们找到这个插入的字母
这道题难度不大,唯一的坑就是,很多人会想,第二个字符串哪个字符第一个里面没有就行,实际上 插入的字符有可能是重复的。
一种思想是:
对第二个字符串的元素,在第一个中出现过,就一次替换成"" 空字符串,这样第二个字符串最后会剩下要找的元素
python代码:
class Solution:
def findTheDifference(self, s, t):
"""
:type s: str
:type t: str
:rtype: str
"""
for i in s :
t=t.replace(i,"",1)
return t
if __name__ == '__main__':
s = Solution()
res = s.findTheDifference("abcd","abcde" )
print(res)