```
class Solution:
# @return a string
def countAndSay(self, n):
prev='1'
for i in range(1,n):
count = 0
now = ''
point_to = 0
while count < len(prev):
point_to = self.find(prev,prev[count],count)
now+= str(point_to)
now+= str(prev[count])
count += point_to
prev = now
return prev
def find(self,sour,res,i):
while sour[i]!=res:
i+=1
j=i
while j<len(sour) and sour[j] == res:
j+=1
return j-i
```