3. Write programs as follows: a. Implement the following functions in a file without using strcpy(), strlen() and strcat(): i. void string_copy (char *destination, char *source)ii. int string_length (char *s) iii. void string_cat (char *destination, char *source) b. Implement a program in another file, which: i. Receives a string from the user as an argument;

ii. Stores the characters of your student number one by one in a char array variable; iii. Prints the above two variables and length of strings (from i and ii), using one printf() statement; and iv. Includes examples to test the above 3 functions, with proper assignments and printf() statements.

4. Write a program that copies a file to another: i. The two file names will be given to the program as arguments from the user. ii. The first file will be copied into the second file. iii. You should compare the two files to see if they are the same. iv. Do not use FILE functions. You must use open(), close(), read() and write().

Need solution for C programming