Total Accepted: 63607 Total Submissions: 237192 Difficulty: Easy
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 { public: string countAndSay(int n) { string s = ""; string res = s; for(int i=0;i<n;i++){ res = ""; int cnt = 1; for(int j=1;j<s.size();j++){ if(s[j]==s[j-1]){ cnt++; }else{ res.push_back(cnt+'0'); res.push_back(s[j-1]); cnt = 1; } } res.push_back(cnt+'0'); if(!s.empty()) res.push_back(s[s.size()-1]); s = res; } cout<<res<<endl; return res; } };
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