[C Programming] Exercises on Types, Operators and Expressions

We cover solution of exercises on types, operators and expressions in book "The C programming language".

Exercise 2-1. Write a program to determine the ranges of char, short, int, and long variables, both signed and unsigned, by printing appropriate values from standard headers and by direct computation. Harder if you compute them: determine the ranges of the various floating-point types.
Solution

Exercise 2-2. Write a loop equivalent to the for loop above without using && or ||.
Solution

Convert s to integer

Convert c to lower case

Pseudo-random generator

Exercise 2-3. Write a function htoi(s), which converts a string of hexadecimal digits (including an optional 0x or 0X) into its equivalent integer value. The allowable digits are 0 through 9, a through f, and A through F.
Solution

Squeeze

Strcat

Exercise 2-4. Write an alternative version of squeeze(s1,s2) that deletes each character in s1 that matches any character in the string s2.
Solution

Exercise 2-5. Write the function any(s1,s2), which returns the first location in a string s1 where any character from the string s2 occurs, or -1 if s1 contains no characters from s2. (The standard library function strpbrk does the same job but returns a pointer to the location.)
Solution

Exercise 2-6. Write a function setbits(x,p,n,y) that returns x with the n bits that begin at position p set to the rightmost n bits of y, leaving the other bits unchanged.
Solution

Exercise 2-7. Write a function invert(x,p,n) that returns x with the n bits that begin at position p inverted (i.e., 1 changed into 0 and vice versa), leaving the others unchanged.
Solution

Exercise 2-8. Write a function rightrot(x,n) that returns the value of the integer x rotated to the right by n positions.
Solution

Bit count

Exercise 2-9. In a two's complement number system, x &= (x-1) deletes the rightmost 1-bit in x. Explain why. Use this observation to write a faster version of bitcount.
Solution

Exercise 2-10. Rewrite the function lower, which converts upper case letters to lower case, with a conditional expression instead of if-else.
Solution