Count and Say

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 n^th sequence.

Note: The sequence of integers will be represented as a string.

1是第一数字。11是第二个数字，输出第n个数字。

class Solution {public:    string countAndSay(int n) {        string temp,result;        result.push_back('1'); //字符串result后面添加1；                int count;        char pre;        for(int i=1;i<n;i++){ //n为2时，只要进行一次，输出11；            temp=result;            result.clear();            pre=temp[0];            count=1;            for(int j=1;j<temp.size();j++){                if(temp[j]==pre)                count++;                else{  //temp[j]与之前的pre不相等，更行results，并把pre移到temp[j]处，打印出tem[j]之前的。                    result.push_back('0'+count);                    result.push_back(pre);                    pre=temp[j];                     count=1;                }            }            result.push_back('0'+count);//添上最后一个结束符            result.push_back(pre);                                 }       return result;            }};