Simple Calculator Using Function

#include<stdio.h>

float add(float num1, float num2);
float sub(float num1, float num2);
float multiple(float num1, float num2);
float division(float num1, float num2);
int s_root(int num1);
int power(int num1);
int main()
{
  float n1,n2,result ;
  printf("Enter Two Numbers ::\n ");

  scanf("%f",&n1);
  scanf("%f",&n2);
  int option ;
   printf("Enter 1 for Addition\nEnter 2 for subtraction \nEnter 3 for Multiplication\nEnter 4 for Division\nEnter 5 for square root \nEnter 6 for power\n");

  scanf("%d",&option);
  switch(option)
  {
  case 1:
    result=add(n1,n2);
    printf(" Addition is %f\n ", result );
    break ;
  case 2 :
    result=sub(n1,n2);
    printf("Subtraction is %f\n",result);
    break ;
  case 3 :

    result=multiple(n1,n2);
    printf("Multiplication is %f\n",result);
    break ;
     case 4 :
    result=division(n1,n2);
    printf("Division is %f",result);
    break ;

     case 5 :
          result=s_root(n1);
    printf("Square root is %f",result);

    break ;
 case 6 :
          result=power(n1);
    printf("Power  is %f",result);

    break ; }
}

    float add(float num1, float num2)
    {
        return num1+num2;
    }
float sub(float num1, float num2)
{
    return num1-num2;

}
float multiple(float num1, float num2)
{
    return num1*num2;
}
float division(float num1, float num2)
{
    return num1/num2;
}
int s_root(int num1)
{
    return sqrt(num1);
}
int power(int num1)
{
    return pow(num1,2);
}