Universal Base Converter

#include <iostream>
#include <string>

using namespace std;

int main()
{
    string number,tempstring;
    int degree_start, degree_end, len,temp,temp2,temp3,temp4;
    string code = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    cout << "Type the number" << endl;
    cin >> number;
    cout << "Type the degree of the number" << endl;
    cin >> degree_start;
    cout << "Type the degree of the converted number" << endl;
    cin >> degree_end;
    len = number.length();
    temp =0;
    for (int c=1;c<=len;c++)
    {
        tempstring=number.substr(len-c+1,1);
        for(int d=1;d<=degree_start;d++)
        {
            if(tempstring==code.substr(d,1))
                temp2 = d;
        }
        temp = temp+(temp2-1)*(degree_start^(c-1));
    }
    tempstring = " ";
    if(temp == 0)
        tempstring = "0";
    while (temp)
    {
        temp3 = temp-degree_end*(temp/degree_end);
        tempstring = code.substr(temp+1,1) + tempstring;
        temp = temp/degree_end;
        if(temp < degree_end)
        {
            tempstring = code.substr(temp+1,1) + tempstring;
            temp = 0;
        }
    }
    cout << "Result:" << tempstring <<endl;

    return 0;
}