have time limit please help me :(

1) Write a C function strsShuffle() that takes three strings (say s1, s2, s3) as parameters, stores into s3 one character from s1 then one char from s2, then next char from s1, next char from 2, ... When all characters of s1 or s2 are used and there are more characters in the other string, then those characters are copied to s3. See examples below.

Example: if s1 is "ABCDEFGH", s2 is "1234", s3 will be "A1B2C3D4EFGH"

Example: if s1 is "ABCD", s2 is "123456", s3 will be "A1B2C3D456"

Prototype: void strsShuffle(char s1[], char s2[], char s3[]);

2) Write a function that changes the places of the first and second nodes of a linked list. I.e. First node will become second node, and the second node will become first node.

THE FUNCTION WILL NOT EXCHANGE DATA, IT WILL CHANGE LINKS.c