C++ || Multi Digit, Decimal & Negative Number Infix To Postfix Conversion & Evaluation The following is sample code which demonstrates the implementation of a multi digit, decimal, and negative number infix to postfix converter and evaluator using a Finite State Machine

REQUIRED KNOWLEDGE FOR THIS PROGRAM

How To Convert Infix To Postfix
How To Evaluate A Postfix Expression
What Is A Finite State Machine?

Using a Finite State Machine, the program demonstrated on this page has the ability to convert and evaluate a single digit, multi digit, decimal number, and/or negative number infix equation. So for example, if the the infix equation of (19.87 * -2) was entered into the program, the converted postfix expression of 19.87 ~2* would display to the screen, as well as the final evaluated answer of -39.74.

NOTE: In this program, negative numbers are represented by the “~” symbol on the postfix string. This is used to differentiate between a negative number and a subtraction symbol.

This program has the following flow of control:

• Get an infix expression from the user
• Convert the infix expression to postfix
• Use a Finite State Machine to isolate all of the math operators, multi digit, decimal, negative and single digit numbers that are found in the postfix expression
• Evaluate the postfix expression using the tokens found from the above step
• Display the evaluated answer to the screen

The above steps are implemented below.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

The following is sample output.

====== RUN 1 ======

==== Infix To Postfix Conversion & Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root
s || Sine
c || Cosine
t || Tangent
~ || Negative Number

Sample Infix Equation: ((s(~4^5)*1.4)/(\$(23+2)-~2.8))*(c(1%2)/(7.28*.1987)^(t23))

Please enter an Infix expression: 12/3*9

The Infix expression = 12/3*9
The Postfix expression = 12 3 /9*

Calculations:
12/3 = 4
4*9 = 36

====== RUN 2 ======

==== Infix To Postfix Conversion & Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root
s || Sine
c || Cosine
t || Tangent
~ || Negative Number

Sample Infix Equation: ((s(~4^5)*1.4)/(\$(23+2)-~2.8))*(c(1%2)/(7.28*.1987)^(t23))

Please enter an Infix expression: -150.89996 - 87.56643

The Infix expression = -150.89996 - 87.56643
The Postfix expression = ~150.89996 87.56643-

Calculations:
-150.9-87.5664 = -238.466

====== RUN 3 ======

==== Infix To Postfix Conversion & Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root
s || Sine
c || Cosine
t || Tangent
~ || Negative Number

Sample Infix Equation: ((s(~4^5)*1.4)/(\$(23+2)-~2.8))*(c(1%2)/(7.28*.1987)^(t23))

Please enter an Infix expression: ((s(~4^5)*1.4)/(\$(23+2)-~2.8))*(c(1%2)/(7.28*.1987)^(t23))

The Infix expression = ((s(-4^5)*1.4)/(\$(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23))
The Postfix expression = ~4 5^ s1.4* 23 2+ \$~2.8-/ 1 2% c7.28 .1987* 23t^/*

Calculations:
-4^5 = -1024
sin(-1024) = 0.158533
0.158533*1.4 = 0.221947
23+2 = 25
√25 = 5
5--2.8 = 7.8
0.221947/7.8 = 0.0284547
1%2 = 1
cos(1) = 0.540302
7.28*0.1987 = 1.44654
tan(23) = 1.58815
1.44654^1.58815 = 1.79733
0.540302/1.79733 = 0.300614
0.0284547*0.300614 = 0.00855389

====== RUN 4 ======

==== Infix To Postfix Conversion & Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root
s || Sine
c || Cosine
t || Tangent
- || Negative Number
Sample Infix Equation: ((s(-4^5)*1.4)/(\$(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23))

Please enter an Infix expression: (1987 + 1991) * -1

The Infix expression = (1987 + 1991) * -1
The Postfix expression = 1987 1991+ ~1*

Calculations:
1987+1991 = 3978
3978*-1 = -3978

C++ || Snippet – Custom Template Linked List Sample Code This page will consist of sample code for a singly linked list, which is loosely based on the built in C++ “List” library. Provided in the linked list class are the following functions:

From the following, the functions of interest to look out for are the “Delete, Display, Replace, InsertBefore, InsertAfter, and InsertInOrder” functions as they are typically used as programming assignments in many C++ Data structures courses to further demonstrate how linked lists operate.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.

Once compiled, you should get this as your output

** These are names of fruits sorted in order using the 'InsertInOrder()' function:

Apple
Orange
Plum
Tomato

There is currently 4 items in the list

** Here is the same list with the word 'Plum' deleted
using the 'Delete()' function:

Apple
Orange
Tomato

There is currently 3 items in the list

** Now the word 'Bike' will be added to the list,
right after the word 'Apple' using the 'InsertAfter()' function:

Apple
Bike
Orange
Tomato

There is currently 4 items in the list

** Now the name 'Jessica' will be added to the list,
right before the word 'Orange' using the 'InsertBefore()' function:

Apple
Bike
Jessica
Orange
Tomato

There is currently 5 items in the list

** The word 'Orange' will now be replaced with the name,
'Kat' using the 'Replace()' function:

Apple
Bike
Jessica
Kat
Tomato

There is currently 5 items in the list

C++ || Snippet – Singly Linked List Custom Template Queue Sample Code This page will consist of sample code for a custom singly linked list template queue. This implementation differs from the previously highlighted doubly linked list in that this version uses a single node to store its data rather than using two separate nodes (front and rear).

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Structs
Classes
Template Classes - What Are They?''
Queue - What is it?
FIFO - First In First Out
#include < queue>
Linked Lists - How To Use

This template class is a custom duplication of the Standard Template Library (STL) queue class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.

Once compiled, you should get this as your output

charQueue has 35 items in it and contains the text:
My Programming Notes Is A Big Help!

intQueue has 12 items in it.
The sum of the numbers in the queue is: -2817

doubleQueue has 11 items in it.
The sum of the numbers in the queue is: 210.777
Press any key to continue . . .

C++ || Snippet – Doubly Linked List Custom Template Queue Sample Code This page will consist of sample code for a custom doubly linked list template queue. This implementation is considered a doubly linked list because it uses two nodes to store data in the queue – a ‘front’ and a ‘rear’ node. This is not a circular linked list, nor does it link forwards and/or backwards.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Structs
Classes
Template Classes - What Are They?
Queue - What is it?
FIFO - First In First Out
#include < queue>
Linked Lists - How To Use

This template class is a custom duplication of the Standard Template Library (STL) queue class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.

Once compiled, you should get this as your output

charQueue has 39 items in it and contains the text:
My Programming Notes Helped Me Succeed!

intQueue has 9 items in it.
The sum of the numbers in the queue is: -2145

floatQueue has 10 items in it.
The sum of the numbers in the queue is: -286.717

C++ || Snippet – Linked List Custom Template Stack Sample Code This page will consist of sample code for a custom linked list template stack. This page differs from the previously highlighted array based template stack in that this version uses a singly linked list to store data rather than using an array.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Structs
Classes
Template Classes - What Are They?
Stacks
LIFO - What Is It?
#include < stack>
Linked Lists - How To Use

This template class is a custom duplication of the Standard Template Library (STL) stack class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.

Once compiled, you should get this as your output

charStack has 31 items in it
and contains the text "My Programming Notes Is Awesome" backwards:
emosewA sI setoN gnimmargorP yM

intStack has 9 items in it.
The sum of the numbers in the stack is: 2145

floatStack has 10 items in it.
The sum of the numbers in the stack is: 286.717

C++ || Stack Based Postfix Evaluation (Single Digit) This page consists of another homework assignment which was presented in a C++ Data Structures course. While the previously discussed program dealt with converting Infix expressions to Postfix, this program will demonstrate exactly how to evaluate them.

NOTE: Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

REQUIRED KNOWLEDGE FOR THIS PROGRAM

What Is Postfix?
How To Convert Infix To Postfix Equations
Stack Data Structure
Cin.getline
How To Evaluate Postfix Expressions
The Order Of Operations
#include "ClassStackType.h"

The title of this page is called – “Stack Based Postfix Evaluation (Single Digit).” Why “single digit?” The program demonstrated on this page has the ability to evaluate a postfix equation, but it only has the ability to evaluate single digit values. What do I mean by that? Consider the infix equation: 5+2. When that expression is converted to postfix, it will come out to be: 52+, and the answer will be 7 (5+2=7). But what if we have an equation like 12+2? When that expression is converted to postfix, it will come out to be: 122+. The postfix conversion is correct, but when you try to evaluate the expression, we do not know if the math operation should be 12+2 or 1+22, it can be read either way.

Question: So why is this program being displayed if it only works for single digits?
Answer: Because it demonstrates the process of evaluating postfix equations very well.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

Before we get into things, here is a helpful algorithm for evaluating a postfix expression in pseudo code:

Once you understand the process of converting from infix to postfix, adding the ability to evaluate multiple digits within this program should be doable.

======= POSTFIX EVALUATION =======

This program uses a custom template.h class. To obtain the code for that class, click here.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compile three separate times to display different output)

====== RUN 1 ======

==== Postfix Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Postfix Equation: 45^14*232+\$2-/12%24*/*

Please enter a postfix expression: 1 2 + 5 6 + /
The postfix expression = 1 2 + 5 6 + /

Calculations:
1+2 = 3
5+6 = 11
3/11 = 0.272727

====== RUN 2 ======

==== Postfix Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Postfix Equation: 45^14*232+\$2-/12%24*/*

Please enter a postfix expression: 35*76^+
The postfix expression = 35*76^+

Calculations:
3*5 = 15
7^6 = 117649
15+117649 = 117664

====== RUN 3 ======

==== Postfix Evaluation ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Postfix Equation: 45^14*232+\$2-/12%24*/*

Please enter a postfix expression: 45^4*32+\$2-/12%24*/*
The postfix expression = 45^4*32+\$2-/12%24*/*

Calculations:
4^5 = 1024
1024*4 = 4096
3+2 = 5
√5 = 2.23607
2.23607-2 = 0.236068
4096/0.236068 = 17350.9
1%2 = 1
2*4 = 8
1/8 = 0.125
17350.9*0.125 = 2168.87

C++ || Stack Based Infix To Postfix Conversion (Single Digit) This page consists of another homework assignment which was presented in a C++ Data Structures course. No matter which institution you attend, it seems every instructor assigns a program similar to this at one time or another.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

REQUIRED KNOWLEDGE FOR THIS PROGRAM

What Is Infix?
What Is Postfix?
Stack Data Structure
Cin.getline
How To Convert To Postfix
The Order Of Operations
#include "ClassStackType.h"

The program demonstrated on this page has the ability to convert a normal infix equation to postfix equation, so for example, if the user enters the infix equation of (1*2)+3, the program will display the postfix result of 12*3+.

Before we get into things, here is a helpful algorithm for converting from infix to postfix in pseudo code:

======= INFIX TO POSTFIX CONVERSION =======

This program uses a custom template.h class. To obtain the code for that class, click here.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compile three separate times to display different output)

====== RUN 1 ======

==== Infix to Postfix Conversion ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Infix Equation: (((4^5)*14)/(\$(23+2)-2))*(1%2)/(2*4)

Please enter an infix expression: ((a+b)+c)/(d^e)
The Infix expression = ((a+b)+c)/(d^e)
The Postfix expression = ab+c+de^/

====== RUN 2 ======

==== Infix to Postfix Conversion ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Infix Equation: (((4^5)*14)/(\$(23+2)-2))*(1%2)/(2*4)

Please enter an infix expression: (3*5)+(7^6)
The Infix expression = (3*5)+(7^6)
The Postfix expression = 35*76^+

====== RUN 3 ======

==== Infix to Postfix Conversion ====

Math Operators:
- || Subtraction
* || Multiplication
/ || Division
% || Modulus
^ || Power
\$ || Square Root

Sample Infix Equation: (((4^5)*14)/(\$(23+2)-2))*(1%2)/(2*4)

Please enter an infix expression: (((4^5)*14)/(\$(23+2)-2))*(1%2)/(2*4)
The Infix expression = (((4^5)*14)/(\$(23+2)-2))*(1%2)/(2*4)
The Postfix expression = 45^14*232+\$2-/12%24*/*

C++ || Snippet – Array Based Custom Template Stack Sample Code This page will consist of sample code for a custom array based template stack.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Classes
Template Classes - What Are They?
Stacks
LIFO - What Is It?
#include < stack>

This template class is a custom duplication of the Standard Template Library (STL) stack class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.