1) Write a C program to swap 2 randomly generated numbers by using call by reference.

Note: please read relevant reference for learning how to randomly generate a number with a seed set up.

2) Write a program in C to store 10 elements in a char array and print the elements using a pointer. The requirements are given as follows,

• define a char array with the letters a~j

• define a pointer and use it for accessing each element in the char array, and print them all out

3)Write a program in C to count the number of vowels in a string using a pointer.

• ask the user to enter a string with a length less than 20

• define a pointer to get access to the above string, go through the whole string and count the number of vowels in it