variables - C++ Constant char -


i built simple calculator out of c++, uses chars, (+,-*,/) works math operators when user inputs '=' does't work.

#include <iostream> #include <string> #include <sstream> #include <math.h>   using namespace std;  #define pi 3.14159265359 #define newline '\n'    void printf(string string) {    cout << string; }  int main () { char operation; double a,b,c, value; double answer = 0; bool more = true;  cout << "welcome calculator\n\ninput value: "; cin >> answer; operations:  cin >> operation;  if (operation != '=') {     if (operation == '+') {         cin >> value;         cout << "\n" << answer << " " << operation << " " << value << "\n";         answer += value;         cout << "equals " << answer << "\n";         cout << answer << " - new operation? ";         goto operations;     }     if (operation == '-') {             cin >> value;             cout << "\n" << answer << " " << operation << " " << value << "\n";             answer -= value;             cout << "equals " << answer << "\n";             cout << answer << " - new operation? ";             goto operations;         }     if (operation == '*') {             cin >> value;             cout << "\n" << answer << " " << operation << " " << value << "\n";             answer *= value;             cout << "equals " << answer << "\n\n";             cout << answer << " - new operation? ";             goto operations;         }     if (operation == '/') {                 cin >> value;                 cout << "\n" << answer << " " << operation << " " << value << "\n";                 answer /= value;                 cout << "equals " << answer << "\n\n";                 cout << answer << " - new operation? ";                 goto operations;             }     if (operation == '^') {                     cin >> value;                     cout << "\n" << answer << " " << operation << " " << value << "\n";                     answer = pow(answer, value);                     cout << "equals " << answer << "\n\n";                     cout << answer << " - new operation? ";                     goto operations;                 }     if (operation == '=') {                     cout << "\nfinal answer = " << answer << "\n\nnew operation [yes/no]: ";                     string check;                     cin >> check;                     if (check == "yes") {                         cout << "\ninput value: ";                         cin >> answer;                          cout << "\n";                         goto operations;                     } else {                         cout << "\ngoodbye now...\n";                         return 0;                     }                  } } else {     cout << "unknown error! program closing...";     return 0; }   return 0; }

when user uses operation besides = works perfectly, if use , equals sign doesn't work.

example program out put:

welcome calculator  input value: 4 +4  4 + 4 equals 8 8 - new operation? - 3  8 - 3 equals 5 5 - new operation? * 5  5 * 5 equals 25  25 - new operation? /2  25 / 2 equals 12.5  12.5 - new operation? ^2  12.5 ^ 2 equals 156.25  156.25 - new operation? = unknown error! program closing... 

if (operation != '=') {     ...     if (operation == '=') {     } }

if operation isn't equal "=" , if it's equal "=". think planned put closure operator or in first outer if.


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