代码
class Solution {
public:
string countAndSay(int n) {
string s = "";
if(n==0)
return s;
for(int i = 1; i <= n; ++i)
s = countAndSayHelper(s);
return s;
}
string countAndSayHelper(string &s)
{
if(s.size()==0)
return "1";
string temp = "";
for(int i = 0; i < s.size(); ++i)
{
int cnt = 1;
while(i+1<s.size()&&s[i]==s[i+1])
{
cnt++;
i++;
}
temp += (cnt+'0');
temp += s[i];
}
return temp;
}
};