--%>

State Measuring complexity

Measuring complexity: Many algorithms have an integer n, or two integers m and n, as input - e.g., addition, multiplication, exponentiation, factorisation and primality testing. When we want to describe or analyse the `easiness' or `hardness' of the algorithm, we want to measure its `running time' as a function of the `size' of the input value(s).

If the input value is n, then it is usual to use the number of (decimal) digits, or bits (binary digits), required to store n as a measure of the size of n.

Given input n, the number of decimal digits in n is given by

[log10 n] +1;

where [x], pronounced `floor of x', denotes the greatest integer less than or equal to x. The number of binary digits or bits is similarly given by

[lg n] +1;

where we use the abbreviation lg x for log2 x (this notation is common, but not completely standard).

   Related Questions in Mathematics

  • Q : Problem on inventory merchandise AB

    AB Department Store expects to generate the following sales figures for the next three months:                            

  • Q : What is Non-Logical Vocabulary

    Non-Logical Vocabulary: 1. Predicates, called also relation symbols, each with its associated arity. For our needs, we may assume that the number of predicates is finite. But this is not essential. We can have an infinite list of predicates, P

  • Q : Graph Theory is the n-Dimensional Qn

    is the n-Dimensional Qn Hamiltonian? Prove tour answer

  • Q : Problem on Datalog for defining

    The focus is on  the use of Datalog for defining properties  and queries on graphs. (a) Assume that P is some property of graphs  definable in the Datalog. Show that P is preserved beneath extensions  and homomo

  • Q : Abstract Algebra let a, b, c, d be

    let a, b, c, d be integers. Prove the following statements: (a) if a|b and b|c. (b) if a|b and ac|bd. (c) if d|a and d|b then d|(xa+yb) for any x, y EZ

  • Q : Examples of groups Examples of groups:

    Examples of groups: We now start to survey a wide range of examples of groups (labelled by (A), (B), (C), . . . ). Most of these come from number theory. In all cases, the group axioms should be checked. This is easy for almost all of the examples, an

  • Q : Problem on augmented matrix Consider

    Consider the following system of linear equations.  (a) Write out t

  • Q : Problem on Fermats method A public key

    A public key for RSA is published as n = 17947 and a = 3. (i) Use Fermat’s method to factor n. (ii) Check that this defines a valid system and find the private key X.

    Q : Problem on mass balance law Using the

    Using the mass balance law approach, write down a set of word equations to model the transport of lead concentration. A) Draw a compartmental model to represent  the diffusion of lead through the lungs and the bloodstream.

  • Q : Solve each equation by factoring A

    A college student invested part of a $25,000 inheritance at 7% interest and the rest at 6%.  If his annual interest is $1,670 how much did he invest at 6%?  If I told you the answer is $8,000, in your own words, using complete sentences, explain how you