LeetCode 504. 七进制数

题目描述链接：https://leetcode-cn.com/problems/base-7/

LeetCode C++解题class Solution {

public:
    string convertToBase7(int num) {
           string res="";
           bool flag=0;
           if(num==0){
               return "0";
           }
           if(num<0){
               flag=1;
               num=-num;
           }
           while(num){
               int temp=num%7;
               res+=temp+'0';
               num/=7;
           }
           if(flag){
               res+='-';
           }
          

          return reverse(res);
           
    }
    string reverse(string str){
       for(int i=0;i<str.size()/2;i++){
               char temp=str[i];
               str[i]=str[str.size()-i-1];
               str[str.size()-i-1]=temp;
        }
        
        return str;
    }


};