AMBATUCOMMIT

memoryaddresses.c

@@ -2,21 +2,26 @@
 #include <stdio.h>
 #include <stdalign.h>
 
+
+
+
 int main(void) {
 
 int integer1 = 1;
-short short2 = 2;
 int integer3 = 3;
+short short2 = 2;
 
-char char1 = 4;   //2
 float float1 = 3.14;  //2
+char char1 = 4;   //2
+
+printf("integer1 =%d Memory address %p\n size = %lu\n",integer1, &integer1, sizeof(integer1));
+//  printf("short2 =%d Memory address%p, size = %lu\n",short2, &short2, sizeof(short2));
+printf("integer3 =%d Memory address %p\n size = %lu\n",integer3, &integer3, sizeof(integer3));
+printf("short2 =%d Memory address %p\n size = %lu\n",short2, &short2, sizeof(short2));
+
+printf("float1 = %d Memory address %p\n size = %lu\n", float1, &float1, sizeof(float1));
+printf("char1 = %d Memory address %p\n size = %lu\n", char1, &char1, sizeof(char1));
 
-printf("integer1 =%d Memory address%p\n",integer1, &integer1);
-printf("size= %d\n", sizeof(integer1));
-printf("short2 =%d Memory address%p\n",short2, &short2);
-printf("integer3 =%d Memory address%p\n",integer3, &integer3);
-printf("char1 = %d Memory address%p\n", char1, &char1);
-printf("float1 = %d Memory address%p\n", float1, &float1);
 
 
 // Exercise Tasks
@@ -33,11 +38,15 @@ printf("float1 = %d Memory address%p\n", float1, &float1);
 //  integer3 =3 Memory address0x7ffeb7370264
 
 // 2 Add a char and a float variable, print out the value and address as above
-
 // 3 Extend each printf to also print out the size of each variable type.
 
-
 // 4 Rearrange the variable declaration order and see if it has an effect on the addresses
+/*  integer1 =1 Memory address000000963e3ff8dc, size = 4
+short2 =2 Memory address000000963e3ff8da, size = 2
+integer3 =3 Memory address000000963e3ff8d4, size = 4
+char1 = 4 Memory address000000963e3ff8d3, size = 1
+float1 = 1610612736 Memory address000000963e3ff8cc, size = 4    */
+
 
 
 //   You may want to rearrange your printfs to match the order of your declarations

pointerchecking.c

@@ -5,13 +5,34 @@ int main () {
 
   int var = 20;       
   int *ip1 = &var;    
-  int *ip2;
+  int *ip2 = NULL;
+
+  if(ip1 != NULL)
+  {
+    printf("Address in ip1 = %p\n", ip1);
+    printf("value in ip1 = %d\n", *ip1);
+  }
+  else
+  {
+    printf("ip2 done out ere\n");
+  }
+
+  if(ip2 != NULL)
+  {
+    printf("Address in ip2 = %p\n", ip2);
+    printf("value in ip2 = %d\n", *ip2);
+  }
+  else
+  {
+    printf("ip2 done out ere\n");
+  }
+
   return 0;
 }
 
 // Exercise Tasks
-// 1 Run the code. What is ip2 pointing at? Is this safe?
-// 2 ip2 might be pointing at an integer. Print out the value ip2 is pointing at as an integer
+// 1 Run the code. What is ip2 pointing at? Is this safe? Points at nothing
+// 2 ip2 might be pointing at an integer. Print out the value ip2 is pointing at as an integer: Prints negative num
 // 3 Initialise ip2 to NULL. Comment out the line printing out ip2 as an integer. Run the code.
 // 4 Uncomment the line you just commented out and run the code. Why doe s the code crash?
 // 5 Add checks before trying to use ip1 or ip2, test to make sure they are not NULL before accessing them.
\ No newline at end of file

pointers.c

@@ -3,8 +3,14 @@
 
 int main () {
 
-  int var = 20;   
-
+  int var = 9000;   // 6 - CHANGED FROM 20
+  int* varPtr = &var;  // 1
+  *varPtr = 8;    // 7
+  printf("%p\n", &var);   // 2
+  printf("%p\n", varPtr);   // 3
+  printf("%d\n", var);    // 4
+  printf("%d\n", *varPtr);    // 5
+ 
   // Exercise tasks
   // 1 Create a pointer variable that stores the address of var
   // 2 Print out the address of var using &var