Question

In the last lab (Lab 5), you wrote a program named seriesFunction.c to compute the value of S(x) for the following series. Your program prompted user to enter two values, x and n. You defined a function to compute the sum of this series. Your function took two arguments, x and n; and returned the sum of the series. S(x) = x + (x+1) + (x+2) + (x+3) + (x+4) + + (x + n -1) + (x + n) As an example, for input values x = 100 and n = 0, it should output 100. For x = 100 and n = 1, it should output 100 + 101 = 201. Your function used the "call by value" technique. For this activity you have to rewrite the function using "call by reference" technique. For this lab, you have to write a program named seriesFunctionCallByReference.c that prompts user to enter two values, x and n. Then it would use a function to compute the sum of the series. It will take three arguments: seriesSum (a pointer variable), x and n. Its return type will be void. By using "call by reference" technique, your function will directly write the sum of series on main function.

Answer 1

1.(a): call by value:

#include <stdio.h>
void sriers(int x,int n)
{
int i,a[100];
for(i=0;i<=n;i++)
{
a[i]=x+10;
}
}

int main(void) {
   int x=100,i,n,a[100];
   printf("enter n value \n");
   scanf("%d",&n);
   for(i=1;i<=n;i++)
   {
   a[i]=x+i;
   }
   sriers(x,n);
   printf("the series \n");
   for(i=1;i<=n;i++)
   {
   printf("a[%d]=%d\t",i,a[i]);
   }
   return 0;
}

1.(b). call by reference

#include <stdio.h>
int a[100];
int serice(int *x,int *n)
{
int i,y;
for(i=0;i<=*n;i++)
{
y=*x;
a[i]=y+i;
}
return a;
}

int main(void) {
   int x=100,i,n;
   printf("enter n value \n");
   scanf("%d",&n);
   for(i=1;i<=n;i++)
   {
   a[i]=x+10;
   }
   serice(&x,&n);
   printf("the series \n");
   for(i=1;i<=n;i++)
   {
   printf("a[%d]=%d\t",i,a[i]);
   }
   return 0;
}