BÀI TẬP LỚN MÔN CẤU TRÚC RỜI RẠC KÝ PHÁP BA LAN NGƯỢC CHO BIỂU THỨC LOGIC

TỔNG LIÊN ĐỒN LAO ĐỘNG VIỆT NAM
TRƯỜNG ĐẠI HỌC TƠN ĐỨC THẮNG
KHOA CÔNG NGHỆ THÔNG TIN

BÀI TẬP LỚN MÔN CẤU TRÚC RỜI RẠC

KÝ PHÁP BA LAN NGƯỢC
CHO BIỂU THỨC LOGIC

Người hướng dẫn: GV NGUYỄN QUỐC BÌNH
Người thực hiện: NGUYỄN VĂN LỘC – 518H0647
VÕ TUẤN LỘC – 518H0390
Lớp

:

18H50302

Khoá

:

22


THÀNH PHỐ HỒ CHÍ MINH, NĂM 2019


TỔNG LIÊN ĐỒN LAO ĐỘNG VIỆT NAM
TRƯỜNG ĐẠI HỌC TƠN ĐỨC THẮNG
KHOA CÔNG NGHỆ THÔNG TIN

BÀI TẬP LỚN MÔN CẤU TRÚC RỜI RẠC

REVERSE POLISH NOTATION
FOR LOGIC EXPRESSION

Người hướng dẫn: GV NGUYỄN QUỐC BÌNH
Người thực hiện: NGUYỄN VĂN LỘC – 518H0647
VÕ TUẤN LỘC – 518H0390
Lớp
: 18H50302
Khố : 22

THÀNH PHỐ HỒ CHÍ MINH, NĂM 2019


4

LỜI CẢM ƠN
Thank you to the lecturer - Mr. Nguyen Quoc Binh, for taking the time and effort to help and
support us to complete this great exercise, he has answered and guided enthusiastically the
necessary knowledge. It is very useful and helpful to help this project complete as expected
and bring value to Ton Duc Thang University with good projects. And I also do not forget to
thank the contributions and companionship of my friend Vo Tuan Loc - Student of Information
Technology, Computer Science Department for taking time and effort to support me to
complete well and on time. degree of this essay report. Sincerely thank you.


5

TÓM TẮT


6

From a variety of sources and documents, this year's HKI (2019-2020)
Discrete Structures exercise deals with the inverse Polish algorithm for
logical expressions, from infix to postfix, postfix to truthtable. The
effect of this algorithm is that it will help the computer, calculate but
the complex expression quickly. The main function of the algorithm is
to calculate the value of the expression, the focus and mainly we
transfer the prime factor ( Infix) in suffix form (Postfix).We have been
researching and learning about parallel Stack and List for the last time,
and we also learn the logical operator functions used to convert Polish
backwards and calculate and create a Truth Table based on the square.
That


7

MỤC LỤC


8

CHƯƠNG 1 – GIỚI THIỆU
ST
T
1

2

HỌ VÀ
TÊN
Nguyễn
Văn
Lộc

Võ
Tuấn
Lộc

MSSV

LỚP

CÔNG VIỆC

518H0647

18H5030
2

- Phân chia việc làm cụ
thể của từng thành viên
-Tìm hiểu và nghiên
cứu phần”Infix to
Postfix”

518H0390

18H0390

THỜI
GIAN
27/10/2019

ĐỊA ĐIỂM
Quán trà sữa và nhà Văn Lộc

31/10/2019

-Viết báo cáo và viết
code

31/10/2019
-7/11/2019

-Tim hiểu và nghiên
cưu phần ’Postfix to
Truthtable”
-Viết code, fix bug và
làm báo cáo

27/10/2019
31/10/2019
31/10/2019
7/11/2019

Quán trà sữa và nhà bạn Văn

Lộc


9

CHƯƠNG 2 – CƠ SỠ LÝ THUYẾT
2.1 Reverse Polish Notation (RPN)
- Reverse Polish Notation - Polish notation
- It is a method of calculation proposed by the mathematician Jan Łukasiewicz around 1920
and it is a way of writing an algebraic expression which is very convenient for performing
mathematical operations.
- Help the computer easily calculate the complex expressions that people need to handle
quickly.
- Is the algorithm used to calculate the expression value, the focus is to bring the expression
from the infix (infix) to the suffix form (postfix).
- The basic feature of this writing is that there is no need to use brackets and always perform
from left to right.
- A method to express expressions in which the operator notation is set after the arguments are
run.
- Basically, the algorithm can be divided into the following two main stages:
• Conversion: normal expression is converted into Polish Kpn form
• Calculation: use the logical operator to calculate the expression value based on the
Polish form of kpnđ
- Logical state: Logically, an entity exists only in one of two states (True or False, 0 or 1)
- Logical variables: used specifically for states of entities. A logical variable is represented by
a symbol (word or sign) and it only accepts one of two values: 0 or 1.

2.2 The theory of basic logic and use to calculate truth values
2.2.1. Unary Operators
Unary operators are the simplest operations because they can be applied to

a single True or False value.
2.2.2.Identity
The identity is our trivial case. It states that True is True and False is False.
2.2.3 Negation


10

The negation operator is commonly represented by a tilde (~) or ¬ symbol. It negates, or
switches, something’s truth value.
We can show this relationship in a truth table. A truth table is a way of organizing information
to list out all possible scenarios.
We title the first column p for proposition. In the second column we apply the operator to p, in
this case it’s ~p (read: not p). So as you can see if our premise begins as True and we negate it,
we obtain False, and vice versa.

Truth Table for Logical Negation in TF and 01 notations

2.2.4 Logical True and Logical False
These are kinda strange operations. Logical true always results in True and logical false always
results in False no matter the premise. These operations are often referred to as “always true”
and “always false”.


11

NOT
NOT
P
~P

P
~P
F
T
F
T
T
F
T
F

P

Q

P^Q

Pv Q

P Q

P Q

T

T

T

T

T

T

T

F

F

T

F

F

F

T

F

T

T

F

F

F

F

F

T

T


12

CHƯƠNG 3 –Thức nghiệm
Our code works like this: First I wrote the PriorityOfOperator function to compare the order of
operations In the Infix2Postfix function. I will create a list and view it as a stack, perform a
loop running on each element in Infix: -If the element is a letter, I will pass it into the Postfix
string -If the element is in parentheses, then I will pass it on the stack -If the element is
enclosed in parentheses, then I will pop the rest of the stack until it meets the opening
parenthesis, stop by giving a while loop as long as the last element of the stack is not opening
parenthesis -If the element is the operator, execute the while loop with the condition that the
stack is not empty and the last element of the stack must not be parentheses, if the current
operator is less than or equal to the operator at the end. in the stack, pop the operator in the
stack and pass it to Postfix then pass the current operator into the stack, otherwise only pass
the current operator into the stack After performing the above loop, I write 1 more loop to pop
all the remaining elements in the stack
Multifunctional Postfix2Truthtable singing, features you love our
In Postfix2Truthtable, you can create a count list of Postfix, a list, a list.
Healthy and wonderful

List Em 1 1 List is a list of him and he sang Postfix, resulting in an upgraded version and a
stack.
Powerful 1 number 1 value and best value and list value (element) in list (element) in list
(element) in list (element) in list of codes (charC, list (element)). The zip () function in Python
answers and locks, is a tuple list iterator that combines elements and repetitive features. Inside,
focused, valuable, valuable, valuable, right, can be on the list
The rest of me
-If I'm a True / False value, overlap


13

-If integrated I am a name:
+ If I am a person not (), meanwhile, he, the other person, after he sings the result
+ In other cases, create two value variables that pop out from the stack, perform logical
calculations based on the CalculatePostfix function and then pass that value back onto the
stack and the result
After performing the above two loops, I will add the result variable to the element at the index
position of Truthtable

TÀI LIỆU THAM KHẢO
Tiếng Việt
1. />2. All the Lab on elit.tdt.edu.vn
Tiếng Anh
3. />