Topcoder SRM583 DIV 2 250

#include <string>
#include <iostream>
using namespace std;



class SwappingDigits
{
public:
    bool notBiggest(string &s,int pos)
    {
        int len=s.length();
        int i=0;
        for (i=pos+1;i<len;i++)
        {
            if (s[i]<s[pos]&&(s[i]!='0'||pos!=0))
            {
                return true;
            }
        }
        return false;
    }
    int findSmallest(string&s,int pos)
    {
        int len=s.length();
        int i=0;
        char c='9';
        int index;
        for (i=len-1;i>pos;i--)
        {
            if (s[i]<c&&(s[i]!='0'||pos!=0))
            {
                c=s[i];
                index=i;
            }
        }
        return index;
    }
    string minNumber(string num)
    {
        int i;
        int len=num.length();
        for (i=0;i<len-1;i++)
        {
            if (notBiggest(num,i))
            {
                int index=findSmallest(num,i);
                char c=num[index];
                num[index]=num[i];
                num[i]=c;
                break;
            }
        }
        return num;
    }
};
int main()
{
    SwappingDigits sol;
    string s;
    while(true)
    {
        cin>>s;
        cout<<sol.minNumber(s)<<endl;
    }
}