#include<stdio.h>
#include<string.h>

/****
 ** Exercise 1: What happens if we print str2 before assigning?
 **
 ** Exercise 2: What happens if we do (man strcpy):
 **   str2 = strcpy(str2, str1);
 ** 
 ** Exercise 3: What happens if we do (man strcpy):
 **   sPtr = strcpy(str2, str1);
 **   Is it valid?
 ** 
 ** Exercise 4: What happens if we do:
 **   sPtr = str1;
 **   strcpy(str2,sPtr);
 **   Is it valid?
 ** 
 ** Exercise 5: During strcmp, what happens if we enter a long string (>10
 ** chars)?
 **
 ** Exercise 6: What kind of error checking do the string functions (strcmp,
 ** strlen, strcpy) do?
 **   i)   Passing an invalid pointer as input -- You will face this problem often
 **   ii)  Exceeding the bounds of memory allocated to the string -- Occurs
 **        often
 **   iii) Exceeding the bounds of string length 
 **   Write programs that demonstrate these vulnerabilities. 
 **   Write preventive mechanisms to make sure that the programs do not crash
 **   (e.g., checking the length of string, length of memory allocated, etc)
 ****/

int main(int argc, char* argv[]){

  char str1[] = "CS220";
  char str2[10];
  char *sPtr;
  int ret;

  printf("str1 =%s\n", str1);
  printf("str2 =%s\n", str2); // Whats the output? Ex 1

  /** Length of the string **/ 
  printf("Length of str1 =%d\n", strlen(str1));

  /** Copy strings **/
  strcpy(str2, str1);

  printf("\nAfter copy\n");
  printf("===================\n");
  printf("str1 =%s\n", str1);
  printf("str2 =%s\n", str2);

  /** strcmp **/
  printf("Enter the string to be compared with string %s: ", str1);
  scanf("%s", str2);
  printf("\nComparing\n");
  printf("===================\n");
  ret = strcmp(str1, str2);
  printf("Comparing strings: %s and %s: ret=%d\n", str1, str2, ret);

  ret = strcmp(str2, str1);
  printf("Comparing strings: %s and %s: ret=%d\n", str2, str1, ret);

  return 0;
}