3 - Control Flow

Exercise 3-1

Our binary search makes two tests inside the loop, when one would suffice (at the price of more tests outside). Write a version with only one test inside the loop and measure the difference in run-time. [1]

My solution

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Official solution

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Exercise 3-2

Write a function escape(s, t) that converts characters like newline and tab into visible escape sequences like \n and \t as it copies the string t to s. Use a switch. Write a function for the other direction as well, converting escape sequences into the real characters. [1]

My solution

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Official solution

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Exercise 3-3

Write a function expand(s1, s2) that expands shorthand notations like a-z in the string s1 into the equivalent complete list abc ... xyz in s2. Allow for letters of either case and digits, and be prepared to handle cases like a-b-c and a-z0-9 and -a-z. Arrange that a leading or trailing - is taken literally. [1]

My solution

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Official solution

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Exercise 3-4

In a two's complement number representation, our version of i toa does not handle the largest negative number, that is, the value of n equal to $-(2^{\text{wordsize} - 1})$. Explain why not. Modify it to print that value correctly, regardless of the machine on which it runs. [1]

My solution

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Official solution

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Exercise 3-5

Write the function itob(n, s, b) that converts the integer n into a base b character representation in the string s. In particular, itob(n, s, 16) formats n as a hexadecimal integer in s. [1]

My solution

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Official solution

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Exercise 3-6

Write a version of itoa that accepts three arguments instead of two. The third argument is a minimum field width; the converted number must be padded with blanks on the left if necessary to make it wide enough. [1]

My solution

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Official solution

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