Sound and complete, Computer Engineering

Assignment Help:

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)


Related Discussions:- Sound and complete

Describe key features of the von neumann architecture, Q. Describe key feat...

Q. Describe key features of the von Neumann Architecture? Describe key features of the von Neumann Architecture: The mainly basic function performed by a computer is exe

Users to run programs at same time, A computer system that allows multiple ...

A computer system that allows multiple users to run programs at similar time   Multi tasking system

Push and pop, i want flowchart for push, pop in stack element and display s...

i want flowchart for push, pop in stack element and display stack and exit

What is meant by latch, Latch is a D- type flip-flop used as a temporary st...

Latch is a D- type flip-flop used as a temporary storage device controlled by a timing signal, which can kept 0 or 1. The primary function of a Latch is data storage. It is used in

Method of spirit duplicating, Method : The master from which the copies wi...

Method : The master from which the copies will be taken is first prepared from a special non-absorbent glazed sheet of paper and special carbon paper which acts as the reproducing

What are the blocks of microprocessor based system, What are the blocks of ...

What are the blocks of microprocessor based system 1.  The Memory and I/O System 2.  The DOS Operating System 3.  The Microprocessor

Describe the external users of system, Q. Describe the External Users of sy...

Q. Describe the External Users of system? External Users: Modern information systems are now reaching beyond the boundaries of traditional business to involve customers and o

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd