. [a] What does this program do?

[b] Rewrite the code using appropriate variable names, indentation, and comments.

#include

main()

{

int a, b, c, d;

a = 0;

while (1)

{

printf ("%d ", a);

printf ("Input? ");

scanf ("%d", &c);

if (c == 0) break;

d = 0;

for (b=1; b<=c; b++)

if (c % b == 0) d++;

if(d==2 || c==1) a = a + c;

}

}