Added return 0 (q2.c) and rewrote print_pol (q3.c)

q2.c

@@ -102,5 +102,6 @@ int main(void)
     printf("strcmp over s1 and s2=%i",strcmp(s1,s2));
     printf("stricmp over s1 and s2=%i",stricmp(s1,s2));
 
+    return 0;
 }
 

q3.c

@@ -55,17 +55,78 @@ void mul_poly(int *a, size_t dega, int *b, size_t degb, int *c)
 
 void print_pol(int *a, size_t deg)
 {
-  while(1)
-    {
-      printf(" +%iX^%i",a[deg],deg);
-      if(deg) deg--;/*TODO: ADD COMMENT*/
+  for (;; deg--)
+  {
+    if (!a[deg])             /* coefficient is zero,   */
+      if (deg) continue;     /* nothing to be printed  */
       else break;
+
+    /* print coefficient */
+    if (deg != 0 && (a[deg] == -1 || a[deg] == 1))
+      printf("%c", (a[deg] < 0 ? '-':'+'));
+    else
+      printf("%+d", a[deg]);
+
+    if (deg != 0)   /* print variable? */
+    {
+      printf("X");
+
+      if (deg != 1) /* print exponent? */
+        printf("^%d", deg);
     }
+    else    /* last term of polynomial */
+      break;
+  }
+
   printf("\n");
 }
 
-
-int main()
+/* This function tests the print_pol() function, it does this by
+   creating arrays holding polynomials, and running the print_pol()
+   function on those arrays. After each call to print_pol(), the 
+   expected result is printed. If the output from print_pol() didn't 
+   match, then print_pol() doesn't work as desired.
+*/
+void test_print_pol(void)
+{
+  int test_case_0[] = {0, -8}; /* -8X */
+  size_t deg0 = (sizeof(test_case_0) / sizeof(*test_case_0)) - 1;
+
+  int test_case_1[] = {-8, -1}; /* -X-8 */
+  size_t deg1 = (sizeof(test_case_1) / sizeof(*test_case_1)) - 1;
+
+  int test_case_2[] = {-1, 0}; /* -1 */
+  size_t deg2 = (sizeof(test_case_2) / sizeof(*test_case_2)) - 1;
+
+  int test_case_3[] = {8, 1}; /* +X+8 */
+  size_t deg3 = (sizeof(test_case_3) / sizeof(*test_case_3)) - 1;
+
+  int test_case_4[] = {1, 8}; /* +8X+1 */
+  size_t deg4 = (sizeof(test_case_4) / sizeof(*test_case_4)) - 1;
+
+  int test_case_5[] = {5, -3, 9}; /* +9X^2-3X+5 */
+  size_t deg5 = (sizeof(test_case_5) / sizeof(*test_case_5)) - 1;
+
+  print_pol(test_case_0, deg0);
+  printf("Expected: -8X\n");
+
+  print_pol(test_case_1, deg1);
+  printf("Expected: -X-8\n");
+
+  print_pol(test_case_2, deg2);
+  printf("Expected: -1\n");
+
+  print_pol(test_case_3, deg3);
+  printf("Expected: +X+8\n");
+
+  print_pol(test_case_4, deg4);
+  printf("Expected: +8X+1\n");
+
+  print_pol(test_case_5, deg5);
+  printf("Expected: +9X^2-3X+5\n");
+}
+
+int main(void)
 {
   int pol1[]={1,1,2};
   size_t deg1=((sizeof pol1)/sizeof(*pol1))-1;