Question

C PROGRAM HELP

create a new file calc.c which implements a simple calculator. The calculator will perform the four basic arithmetic operations +, -, * and /. The program should prompt the user for the operation to perform in an endless loop. For example:

calc > 3 + 6
9
calc >

You must implement the calculator such that there is one calc function which takes as arguments the numerical values of the two operands and a pointer to the specified function (add for +, etc), plugs the two values into the referenced function, and returns the result.

Your program should work independent of spaces in the input. For instance, both 1+2 and 1 + 2 should work. This is actually very easy to do with scanf, check out its manual page!

Answer 1

If you have any doubts, please give me comment...

#include<stdio.h>

int calc(int n1, int n2, int (*fun)(int, int));

int add(int n1, int n2);

int subtract(int n1, int n2);

int multiply(int n1, int n2);

int division(int n1, int n2);

int main(){

int n1, n2;

char op;

int result;

while(1){

printf("calc > ");

scanf("%d %c %d", &n1, &op, &n2);

switch(op){

case '+':

printf("%d", calc(n1, n2, add));

break;

case '-':

printf("%d", calc(n1, n2, subtract));

break;

case '*':

printf("%d", calc(n1, n2, multiply));

break;

case '/':

printf("%d", calc(n1, n2, division));

break;

default:

printf("Invalid operation");

}

printf("\n");

}

return 0;

}

int calc(int n1, int n2, int (*fun)(int, int)){

return (*fun)(n1, n2);

}

int add(int n1, int n2){

return n1+n2;

}

int subtract(int n1, int n2){

return n1-n2;

}

int multiply(int n1, int n2){

return n1*n2;

}

int division(int n1, int n2){

return n1/n2;

}