1023. Have Fun with Numbers (20)

#include<iostream>
#include<string>
#include<algorithm>
using namespace std;
string double_str(string str)
{
int temp=0;
for (auto it = str.rbegin();it != str.rend();it++)
{
if ((*it - '0') * 2 + temp > 9)
{
*it = (*it - '0') * 2 + temp - 10 + '0';
temp = 1;
}
else
{
*it=(*it - '0') * 2 + temp  + '0';
temp = 0;
}
}
if (temp == 1) str.insert(str.begin(), '1');
return str;
}
int main()
{
string str1, str2,str3;
cin >> str1;
str2 = double_str(str1);
str3 = str2;
sort(str1.begin(), str1.end());
sort(str2.begin(), str2.end());
if (str1 == str2) cout << "Yes" << endl<<str3 << endl;
else cout << "No" << endl << str3 << endl;
}