c++ - save while loop information after y/n response -

i having problem code can't figure out how fix it.

i have made calculator in c++ using dev-c++. made while loop user doesn't have restart program use again. trying add ability calculated answer used in next calculation code being skipped.

#include <cstdlib> #include <iostream>  using namespace std;  int main(int argc, char *argv[]) {     string username;     float num1, num2, answer;     string berekening;     string again;     float oldanswer;     string oldanswerq;      oldanswer = answer;     again = "y";      cout << "hello you?" << endl;     cout << "" << endl;     cin >> username;      cout << "" << endl;     cout << "well hello " << username << endl;     cout << "" << endl;     while (again == "y"){          if (oldanswer == 0) {             cout << "what first number wanna put in " << username << endl;             cout << "" << endl;             cin >> num1;         }          else {             cout << "do wanna use old answer? y/n" << endl;             cout << "" << endl;             cin >> oldanswerq;         }          cout << "" << endl;         cout << "+, -, x or ÷(u can use / instead of ÷" << endl;         cout << "" << endl;         cin >> berekening;          cout << "" << endl;         cout << "and second number " << username << endl;         cout << "" << endl;         cin >> num2;          cout << "" << endl;         if (berekening == "+"){             answer = num1 + num2;         }          else if (berekening == "-"){             answer = num1 - num2;         }          else if (berekening == "x"){             answer = num1 * num2;         }          else if (berekening == "/"){             answer = num1 / num2;         }          else if (berekening == "÷"){             answer = num1 / num2;         }          cout << username << ", choosed " << berekening << " did was: " << num1 << berekening << num2 << "=" << answer << endl;         cout << "" << endl;         cout << username << ", wanna go again? y/n" << endl;         cout << "" << endl;         cin >> again;         cout << "" << endl;     } } 

i new c++ , welcome suggested improvements.

you set oldanswer equal newanswer outside loop, should done inside loop.

you should not use == when comparing float equal (decimals can accurate number of places on computer)