Write a simple calculator program in c using functions

#include<stdio.h>

#include<conio.h>

void main()

{

int a,b;

int sum(int,int);

int sub(int,int);

int mul(int,int);

float div(float,float);

int mod(int,int);

printf("Enter two numbers: ");

scanf("%d%d",&a,&b);

printf("Sum=%d\n",sum(a,b));

printf("Difference=%d\n",sub(a,b));

printf("multiplication=%d\n",mul(a,b));

printf("Division=%f\n",div(a,b));

printf("Modular division=%d\n",mod(a,b));

getch();

}

int sum(int a,int b)

{

return(a+b);

}

int sub(int a,int b)

{

return(a-b);

}

int mul(int a,int b)

{

return(a*b);

}

float div(float a,float b)

{

return(a/b);

}

int mod(int a,int b)

{

return(a%b);

}