leetcode38. Count and Say
class Solution {
public:
string countAndSay(int n) {
if(n<=1) return "1";
string lower = countAndSay(n-1);
int left = 0;
int num = lower[0];
int numLen = 0;
string newString = "";
while(left<lower.size()){
if(num==lower[left]){
numLen++;
left++;
}else{
newString += string(1,(numLen+'0'))+string(1,num);
numLen = 1;
num = lower[left];
left++;
}
}
newString += string(1,(numLen+'0'))+string(1,num);
return newString;
}
};