SRM 583 Div II Level One：SwappingDigits

#include <iostream>
#include <string>

using namespace std;

string minstr = "";

class SwappingDigits
{
public: string minNumber(string num);
};

string SwappingDigits::minNumber(string num)
{
string temp;
string mins = "";
for (int i = 0; i < num.size()-1; i++) {
for (int j = i+1; j < num.size(); j++) {
temp = num;
swap(temp[i], temp[j]);
if (temp[0] != '0' && mins == "") {
mins = temp;
} else {
if (temp[0] != '0' && temp < mins) {
mins = temp;
}
}
}
}

return mins;
}