Some fixes/extensions of chapter 7 comments

ch_7/task_04/main.c

@@ -14,7 +14,6 @@
 #include <stdio.h>
 
 int average (int val1, int val2) { return val1 + val2 / 2; }                    // function returns int, but result of calculation may be with decimal places
-                                                                                // additionally it is advisable to always provide function prototypes
 
 int main (int argc, char** argv) {                                              // argc & argv are not used within this program
     char number1 = 15;

ch_7/task_05/main.c

@@ -20,6 +20,6 @@ int main (int argc, char** argv) {
     scanf("%c",&answer);
     if (answer == 'n') {
         printf("What do you want then? ");
-        scanf("%s",maoam);
+        scanf("%s",maoam);                                                      // scanf with "%s" implies to danger of buffer overflows
     }
 }                                                                               // main function has return type int, but return statement is missing

ch_7/task_06/main.c

@@ -15,7 +15,7 @@
 
 int main (int argc, char** argv) {                                              // argc & argv are not used within this program
     char animal[] = 'frog';                                                     // strings are denoted with "", '' are only applicable for single character
-    int count = sizeof(animal);
+    int count = sizeof(animal);                                                 // it is advisable to always take into account the size of the variable type in sizeof()
     for (int i=0; i <= count; i++);                                             // semicolon after loop head ends the loop ...
         printf("%d letter: %c\n",i,*animal+i);                                  // ... therefore this statement is executed only once
                                                                                 // loop head run condition has an off-by-one error, since the maximum index of animal is (count-1) ...

ch_7/task_08/main.c

@@ -13,7 +13,7 @@
 
                                                                                 // required includes are missing (i.e., <stdio.h>)
 
-int* get_double (int value) {                                                   // it is advisable to always provide function prototypes
+int* get_double (int value) {
     value *= 2;
     return &value;                                                              // the memory location of value is automatically freed after leaving the function
                                                                                 // therefore its address is invalid afterwards
@@ -23,7 +23,7 @@ int main (int argc, char** argv) {
     int number = 42;
     int* number2x = get_double(number);
     printf("Double a value using an own function!\n");
-    printf("The double of %d is %d!\n",number,*number2x);
+    printf("The double amount of %d is %d!\n",number,*number2x);
     
     return 0;
 }

ch_7/task_09/main.c

@@ -15,7 +15,7 @@
 
 int check = 0;
 
-void check_input (int value, int guess) {                                       // it is advisable to always provide function prototypes
+void check_input (int value, int guess) {
     int check = value == guess ? 1 : 0;                                         // declaration of local variable check shadows global variable
     return;
 }