// File: FnAsArg.cpp
// Example of passing function as parameter
// Prepared by Dr. Spiegel

#include <stdio.h>
#include "char_ops.h"

void GetNumbers(int *X,int *Y);
void OperateOnNumbers(int N1,int N2);

int main()
{int N1,N2;
 char Choice;
 GetNumbers(&N1,&N2);
 OperateOnNumbers(N1,N2);
}


void GetNumbers(int *X,int *Y)
{printf("Enter two Integers >");
 scanf("%d%d",X,Y);
}

int Add(int N1,int N2)
{return(N1+N2);}

int Sub(int N1,int N2)
{return(N1-N2);}

int Mul(int N1,int N2)
{return(N1*N2);}

int Div(int N1,int N2)
{return(N1/N2);}

int Mod(int N1,int N2)
{return(N1%N2);}

int Operate(int N1,int N2,int (*BinaryOp)(int,int))
{return((*BinaryOp)(N1,N2));
}

void OperateOnNumbers(int N1,int N2)
{char Choice;
 do {
  printf("Pick Operation: + - * / %   Q Quits\n");
  Choice=GetChoice("+-*/%Q");
  switch(Choice) {
   case '+': printf("%d + %d = %d\n",N1,N2,Operate(N1,N2,Add)); break;
   case '-': printf("%d - %d = %d\n",N1,N2,Operate(N1,N2,Sub)); break;
   case '*': printf("%d * %d = %d\n",N1,N2,Operate(N1,N2,Mul)); break;
   case '/': printf("%d / %d = %d\n",N1,N2,Operate(N1,N2,Div)); break;
   case '%': printf("%d %% %d = %d\n",N1,N2,Operate(N1,N2,Mod)); break;
  }
 } while (Choice != 'Q');
}