Program in C using function to find the area of circle

\* C Program using function to find the area of circle *\

# include < stdio.h >
# include < conio.h >
float   area(float) ;

int   main( )
{

float r, ar = 0.0 ;
printf(" Enter the radious of circle : ") ;
scanf("%f", &r) ;
ar = area(r) ;
printf("\n Area of circle : %f ", ar) ;
return (0);

}

float   area(float r)
{

float ar ;
ar = 3.14 * r * r ;
return ar ;

}