#include <stdio.h>
#include <math.h>
 
int option;
char q;
int number;
int currentsum;
int value;
 
void calc()
{
     printf("\t\t\t\t\tBegin\n"); // says begin in top middle of screen
     option = 0; number = 0; currentsum = 0; value = 0;
     while(1){
              value = getchar(); // gets user input and sets equal to value
              if (value >= '0' && value <= '9')
              {
                 number = number*10 + (value - '0'); /* a way of reading the "values" left to right. If someone puts in 729 as their first number then it will go across
              and do number = 0*10 (because number was set equal to 0) + 7. then it goes through again. number is now 7 so it goes through and does 7*10 + 2 thus making
              72. Number is now 72 which means it goes 72*10 + 9 making number 729. It will follow this process if the input is a number 1-9*/
              }
              if (value == '+' || value == '-' || value == '*' || value == '/' || value == '^' || value == '=' || value == '\n')
              {
                   if(value == '+') currentsum = currentsum + number; // if I come across one of these symbols then it performs the operation described
                   if(value == '-') currentsum = currentsum - number;
                   if(value == '*') currentsum = currentsum * number;
                   if(value == '/') currentsum = currentsum / number;
                   if(value == '^') currentsum = pow(currentsum, number);
                   if(value == '=') printf(currentsum);  // when it reads an equal sign or a new line it displays the result of the equation.
                   if(value == '\n') printf(currentsum);
              }
              else break; // come across any other symbols or characters break the loop     
             }
}
int main()
{
    system("title Calculator"); // titles windo "Calculator
    system("color 1A"); // makes background blue
    calc(); // goes to void calc
    system("pause");
    scanf("%c",&q);
    if( q == 'q')exit(0);
}