the-c-programming-language-chapter-2

Table of Contents

C Programming Language Chapter 2

Chapter 2

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.

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Exercise 2-2

Write a loop equivalent to the for loop above without using && or ||.

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Exercise 2-3

Write the 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.

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Exercise 2-4

Write an alternate version of squeeze(s1,s2) that deletes each character in the string s1 that matches any character in the string s2.

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Exercise 2-5

Write the function any(s1,s2) , which returns the first location in the 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.)

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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.

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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.

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Exercise 2-8

Write a function rightrot(x,n) that returns the value of the integer x rotated to the right by n bit positions.

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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.

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Exercise 2-10

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

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