Sound and complete, Computer Engineering

Dictator Dim wants to replace counting, in particular, counting the population of his land. To keep an accurate population count, Dictator Dim has instructed his secretary to add one + symbol to a record each time a citizen is born, and one - symbol to the record whenever a citizen dies. This has been going on ever since his rule began.

Dictator Dim is not concerned so much with the actual total population of his lands, just with the net change in population since his rule began. He would be forever disgraced if the net population change were ever negative. Refusing to solve this problem by counting, Dictator Dim instructs his secretary to find a sound and complete logic for the subset of all records that would not disgrace him.
More formally, define the following truth concept WFF's = {+; -}, i.e., all strings composed of only plus and minus symbols.
A WFF x is true if every prefix of x contains at least as many + symbols as - symbols.

Find a logic for this truth concept by proving that it is sound and complete. Hint: it may help to define additional judgement form(s)

Posted Date: 3/21/2013 1:55:44 AM | Location : United States







Related Discussions:- Sound and complete, Assignment Help, Ask Question on Sound and complete, Get Answer, Expert's Help, Sound and complete Discussions

Write discussion on Sound and complete
Your posts are moderated
Related Questions
Differentiate between Protection and Security Operating system contains a collection of objects, hardware or software. Every object has a unique name and can be accessed via a

In the case of Static call, the called program is a stand-alone program, it is an executable program. During run time we can call it in our called program. As about Dynamic call, t

Question 1: (a) How would you explain human reasoning? (b) Explain the different types of human reasoning? Question 2: (a) What are the computational factors affec

Explain Public Switched Telephone Network. PSTN (Public Switched Telephone Network): This is Public Switched Telephone Network (PSTN), which accommodates two types of subscri

Question: (a) Explain the three categories of design patterns. Give two examples from each category. (b) When describing a pattern what is the purpose of "The Intent", an

What controls the screen flow? The SET SCREEN and LEAVE SCREEN statements controls screen flow.

Instruction Stream and Data Stream The term 'stream' indicates to a series or flow of either instructions or data operated on by computer. In the entire cycle of instruction ex

How many "true" terrorists are there in the US?  I don't know, but let's suppose that there are 3000 out of a total population of, say, 3,000,000.  That is, one person in 100,000 i

Why we need to construct state transition diagram Basically you need to construct a state transition diagram for each object with important behaviour. You need not construct on

Matlab already handles naturally easy LaTeX encodings that permit introducing Greek lettters or modifying the font size and appearance in plots.