Lab Practice Quiz 4 1. Kernighan and Ritchie strcmp.c (page 106) Write the function int strcmp(char cs[], char ct[]) compares string cs to string ct and returns <0 if cs0 is cs > ct. With the addition of your function, the program below should output a negative number ( 13 would be OK). #include int strcmp(char s[], char t[]); main() { char s[] = "This is the first string"; char t[] = "This is the second string"; printf("%d\n", strcmp(s, t)); } 2. Kernighan and Ritchie strcpy.c (page 105, 106) Write the function char *strcpy(char s[], char t[]) that copies string t to string s, returning s. With the addition of your function, the program below should output "This is the string" followed by "This is the string". #include char *strcpy(char s[], char t[]); main() { char s[100]; char t[] = "This is the string"; printf("%s\n", strcpy(s, t)); printf("%s\n", s); } 3. Kernighan and Ritchie strlen.c (page 39, 99, 103) Write the function int strlen(char s[]) which returns the length of string s (excluding the terminal '\0'). With the addition of your function, the program below should output 18 #include int strlen(char s[]); main() { char s[] = "This is the string"; printf("%d\n", strlen(s)); } 4. Kernighan and Ritchie swap.c (page 88, 96, 110, 121) swap swap two integers. With your program swap, the following should print "20 10". #include void swap(int *x, int *y); main() { int a = 10, b = 20; swap (&a, &b); printf("%d %d\n", a, b); }