#include
#include
int calsum (intx , inty , intz);
int main()
{
int a , b , c , sum ;
printf("enter no. \n");
scanf("%d %d %d",&a,&b,&c);
sum=calsum(a , b , c);
printf("sum= %d \n" , sum);
return 0;
}
int calsum (intx , inty , intz)
{
int d;
d=x+y+z;
return(d);
}

why this not working