Code to make Simple Calculator in C programming using functions
#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<stdlib.h>
#define KEY "Enter the calculator Operation you want to do:"
void addition();
void subtraction();
void multiplication();
void division();
void modulus();
void power();
int factorial();
void calculator_operations();
int main()
{
int X=1;
char Calc_oprn;
calculator_operations();
while(X)
{
printf("\n");
printf("%s : ", KEY);
Calc_oprn=getche();
switch(Calc_oprn)
{
case '+': addition();
break;
case '-': subtraction();
break;
case '*': multiplication();
break;
case '/': division();
break;
case '?': modulus();
break;
case '!': factorial();
break;
case '^': power();
break;
case 'H':
case 'h': calculator_operations();
break;
case 'Q':
case 'q': exit(0);
break;
case 'c':
case 'C': system("cls");
calculator_operations();
break;
default : system("cls");
printf("\n\tYou have entered unavailable option");
printf("\n");
printf("\n\tPlease Enter any one of below available options\n");
calculator_operations();
}
}
}
void calculator_operations()
{
printf("\n Welcome to C calculator \n\n");
printf("------ Press 'Q' or 'q' to quit the program ------\n");
printf("------ Press 'H' or 'h' to display below options ------\n\n");
printf("Enter 'C' or 'c' to clear the screen and choose below option \n\n");
printf("Enter + symbol for Addition \n");
printf("Enter - symbol for Subtraction \n");
printf("Enter * symbol for Multiplication \n");
printf("Enter / symbol for Division \n");
printf("Enter ? symbol for Modulus\n");
printf("Enter ^ symbol for Power \n");
printf("Enter ! symbol for Factorial \n\n");
}
void addition()
{
int n, total=0, k=0, number;
printf("\nEnter total elements you want to add:");
scanf("%d",&n);
printf("Please enter %d numbers one by one: \n",n);
while(k<n)
{
scanf("%d",&number);
total=total+number;
k=k+1;
}
printf("Sum of %d numbers = %d \n",n,total);
}
void subtraction()
{
int a, b, c = 0;
printf("\nPlease enter first number : ");
scanf("%d", &a);
printf("Please enter second number : ");
scanf("%d", &b);
c = a - b;
printf("\n%d - %d = %d\n", a, b, c);
}
void multiplication()
{
int a, b, mul=0;
printf("\nPlease enter first numb : ");
scanf("%d", &a);
printf("Please enter second number: ");
scanf("%d", &b);
mul=a*b;
printf("\nMultiplication of entered numbers = %d\n",mul);
}
void division()
{
int a, b, d=0;
printf("\nPlease enter first number : ");
scanf("%d", &a);
printf("Please enter second number : ");
scanf("%d", &b);
d=a/b;
printf("\nDivision of entered numbers=%d\n",d);
}
void modulus()
{
int a, b, d=0;
printf("\nPlease enter first number : ");
scanf("%d", &a);
printf("Please enter second number : ");
scanf("%d", &b);
d=a%b;
printf("\nModulus of entered numbers = %d\n",d);
}
void power()
{
double a,num, p;
printf("\nEnter two numbers to find the power \n");
printf("number: ");
scanf("%lf",&a);
printf("power : ");
scanf("%lf",&num);
p=pow(a,num);
printf("\n%lf to the power %lf = %lf \n",a,num,p);
}
int factorial()
{
int i,fact=1,num;
printf("\nEnter a number to find factorial : ");
scanf("%d",&num);
if (num<0)
{
printf("\nPlease enter a positive number to");
printf(" find factorial and try again. \n");
printf("\nFactorial can't be found for negative");
printf(" values. It can be only positive or 0 \n");
return 1;
}
for(i=1;i<=num;i++)
fact=fact*i;
printf("\n");
printf("Factorial of %d is : %d\n",num,fact);
return 0;
}
Output:
