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.
Exercise 2-2.Write a loop equivalent to the for loop above without using && or || .
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 .
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 .
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.)
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.
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.
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.
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 .
Exercise 2-10.Rewrite the function lower, which converts upper case letters to lower case, with a conditional expression instead of if-else .
最終更新：2009年11月21日 20:07
