The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...
1
is read off as "one 1"
or 11
.11
is read off as "two 1s"
or 21
.21
is read off as "one 2
, then one 1"
or 1211
.
Given an integer n, generate the nth sequence.
Note: The sequence of integers will be represented as a string.
class Solution(object): def countAndSay(self, n): """ :type n: int :rtype: str """ li=['1'] newli=['1'] for i in range(1,n): newli=[] count= 0 temp= li[0] for x in li: if x==temp: count+=1 else: newli.append(str(count)) newli.append(temp) temp = x count = 1 else: newli.append(str(count)) newli.append(temp) li=newli return ''.join(newli)