Tag Archives: c++

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.

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:
+ || Addition
- || 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

Final answer = 36

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

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

Math Operators:
+ || Addition
- || 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

Final answer = -238.466

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

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

Math Operators:
+ || Addition
- || 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

Final answer = 0.00855389

C++ || Snippet – How To Override The Default Signal Handler (CTRL-C)

The following is sample code which demonstrates the use of the “signal” function call on Unix based systems.

Signals are interrupts delivered to a process by the operating system which can terminate a program prematurely. You can generate interrupts by pressing Ctrl+C. The “signal” function call receives two arguments. The first argument is an integer which represents the signal number, and the second argument is a pointer to the user defined signal handling function.

The following program catches the “SIGINT” signal number using the signal() function.


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:

Please press CTRL-C

^C Haha I have 10 lives!
^C Haha I have 9 lives!
^C Haha I have 8 lives!
^C Haha I have 7 lives!
^C Haha I have 6 lives!
^C Haha I have 5 lives!
^C Haha I have 4 lives!
^C Haha I have 3 lives!
^C Haha I have 2 lives!
^C Haha I have 1 lives!
^C ** Ahh you got me...

C++ || Snippet – How To Convert A Decimal Number Into Binary

This page will demonstrate how to convert a decimal number (i.e a whole number) into its binary equivalent. So for example, if the decimal number of 26 was entered into the program, it would display the converted binary value of 11010.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

How To Count In Binary
The "Long" Datatype - What Is It?
While Loops
Online Binary to Decimal Converter - Verify For Correct Results
How To Reverse A String

If you are looking for sample code which converts binary to decimal, check back here soon!


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.

Once compiled, you should get this as your output
Note: The code was compiled 3 separate times to display different output

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

Please enter an integer value: 1987

The integer value of 1987 = 11111000011 in binary

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

Please enter an integer value: -26

The integer value of -26 = -11010 in binary

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

Please enter an integer value: 12345678910

The integer value of 12345678910 = 1011011111110111000001110000111110 in binary

C++ || Snippet – Simple Linked List Using Delete, Insert, & Display Functions

The following is sample code for a simple linked list, which implements the following functions: “Delete, Insert, and Display.”

The sample code provided on this page is a stripped down version of a more robust linked list class which was previously discussed on this site. Sample code for that can be found here.

It is recommended you check that out as the functions implemented within that class are very useful.


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.

Once compiled, you should get this as your output

My Programming Notes

My Programming Notes
Is An Awesome Site!
August

[DELETE THE TEXT "AUGUST"]

My Programming Notes
Is An Awesome Site!

Destroying nodes...
My Programming Notes
Is An Awesome Site!

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()' funciton:

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()' funciton:

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 – How To Swap Two Numbers Without Using A Third “Temporary” Variable

The following are three programs which demonstrates how to swap two numbers without using a third “temporary” variable.

Why would anyone want to swap two numbers without utilizing a third variable? There is no real reason to do so other than the fact that exercises such as these are typically used as programming assignments/interview questions. This is a technique that’s rarely ever practical in a real world setting, but it is still an interesting task nonetheless.

SAMPLE OUTPUT:

Please enter two numbers: 7 28

Item #1 = 7
Item #2 = 28

Switching the numbers..

Item #1 = 28
Item #2 = 7


SAMPLE OUTPUT:

Please enter two numbers: 5 12453

Item #1 = 5
Item #2 = 12453

Switching the numbers..

Item #1 = 12453
Item #2 = 5


SAMPLE OUTPUT:

Please enter two numbers: 2132 6547546

Item #1 = 2132
Item #2 = 6547546

Switching the numbers..

Item #1 = 6547546
Item #2 = 2132

C++ || Snippet – Palindrome Checker Using A Stack & Queue

This page consists of a sample program which demonstrates how to use a stack and a queue to test for a palindrome. This program is great practice for understanding how the two data structures work.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Structs
Classes
Template Classes - What Are They?
Stacks
Queues
LIFO - Last In First Out
FIFO - First In First Out
#include 'SingleQueue.h'
#include 'ClassStackListType.h'

This program first asks the user to enter in text which they wish to compare for similarity. The data is then saved into the system using the “enqueue” and “push” functions available within the queue and stack classes. After the data is obtained, a while loop is used to iterate through both classes, checking to see if the characters at each location within both classes are the same. If the text within both classes are the same, it is a palindrome.

NOTE: This program uses two custom template.h classes. To obtain the code for both class, click here and here.


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.

Once compiled, you should get this as your output
(Note: The code was compiled 2 separate times to demonstrate different output)

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

Enter in some text to see if its a palindrome: StEP on No pETS

StEP on No pETS is a palindrome!

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

Enter in some text to see if its a palindrome: Hello World

Hello World is NOT a palindrome..

C++ || Convert Numbers To Words Using A Switch Statement

This program demonstrates more practice using arrays and switch statements.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Integer Arrays
Cin.get
Isdigit
For loops
While Loops
Switch Statements - How To Use

Using “cin.get(),” this program first asks the user to enter in a number (one at a time) that they wish to translate into words. If the text which was entered into the system is a number, the program will save the user input into an integer array. If the text is not a number, the input is discarded. After integer data is obtained, a for loop is used to traverse the integer array, passing the data to a switch statement, which translates the number to text.

This program is very simple, so it does not have the ability to display any number prefixes. As a result, if the number “1858” was entered into the system, the program would output the converted text: “One Eight Five Eight.”


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.

Once compiled, you should get this as your output
Note: The code was compiled four separate times to display different output

======= Run #1 =======

Enter number: 77331

Seven Seven Three Three One

======= Run #2 =======

Enter number: 234-43-1275

Two Three Four Four Three One Two Seven Five

======= Run #3 =======

Enter number: 1(800) 123-5678

One Eight Zero Zero One Two Three Five Six Seven Eight

======= Run #4 =======

Enter number: This 34 Is 24 A 5 Number 28

Three Four Two Four Five Two Eight

C++ || Char Array – Palindrome Number Checker Using A Character Array, Strlen, Strcpy, & Strcmp

The following is a palindromic number checking program, which demonstrates more use of character array’s, Strlen, & Strcmp.

Want sample code for a palindrome checker which works for numbers and words? Click here.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays
How to reverse a character array
Palindrome - What is it?
Strlen
Strcpy
Strcmp
Isdigit
Atoi - Convert a char array to a number
Do/While Loops
For Loops

This program first asks the user to enter a number that they wish to compare for similarity. If the number which was entered into the system is a palindrome, the program will prompt a message to the user via cout. This program determines similarity by using the strcmp function to compare two arrays together. Using a for loop, this program also demonstrates how to reverse a character array, aswell as demonstrates how to determine if the text contained in a character array is a number or not.

This program will repeatedly prompt the user for input until an “exit code” is obtained. The designated exit code in this program is the number 0 (zero). So the program will not stop asking for user input until the number 0 is entered into the program.


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.

Once compiled, you should get this as your output

Enter a positive integer, or (0) to exit: L33T

*** error: "L33T" is not an integer

Enter a positive integer, or (0) to exit: -728

*** error: -728 must be greater than zero

Enter a positive integer, or (0) to exit: 1858

1858 is NOT a Palindrome!

Enter a positive integer, or (0) to exit: 7337

7337 is a Palindrome..

Enter a positive integer, or (0) to exit: 0

Exiting program...

BYE!

C++ || Convert Time From Seconds Into Hours, Min, Sec Format

Here is another simple programming assignment. This page will demonstrate how to convert time from -seconds- into HH::MM::SS (hours, minutes seconds) format. So for example, if you had an input time of 9630 seconds, the program would display the converted time of 2 hours, 40 minutes, and 30 seconds.

Using simple math, this program utilizes the modulus operator, and the division operator during the conversion process.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Modulus - What is it?
How Many Seconds Are In One Hour?
How Many Seconds Are In One Minute?


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.

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

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

Enter a time in seconds: 9630

The time in HH:MM:SS format is: 2 hours, 40 minutes, and 30 seconds!

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

Enter a time in seconds: 7200

The time in HH:MM:SS format is: 2 hours, 0 minutes, and 0 seconds!

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

Enter a time in seconds: 45

The time in HH:MM:SS format is: 0 hours, 0 minutes, and 45 seconds!

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

Enter a time in seconds: 134

The time in HH:MM:SS format is: 0 hours, 2 minutes, and 14 seconds!

====== RUN 5 ======

Enter a time in seconds: 31536000

The time in HH:MM:SS format is: 8760 hours, 0 minutes, and 0 seconds!

C++ || Char Array – Determine If A String Is A Number Or Not

The following is another intermediate homework assignment which was presented in a C++ programming course. This program was assigned to introduce more practice using and manipulating character arrays.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays
Cin.getline
Strlen - Get The Length Of A Char Array
Isalpha
Isspace

This program first prompts the user to input a line of text. After it obtains data from the user, using a for loop, it then displays the the string to the screen one letter (char) at a time. If the current character at that specific array index is a letter, a “flag” is set, indicating that the current word which is being displayed is not a number. If the “flag” is not set, the current word is indeed a number.

This program has the ability to intake multiple words at a time, so for example, if the user input was “Hello World 2012” the program would display the output:

Hello is NOT a number!
World is NOT a number!
2012 is a number..


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.

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

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

Enter some text to see if its a number or not: My Programming Notes

My is NOT a number! There are 2 letters in that word...
Programming is NOT a number! There are 11 letters in that word...
Notes is NOT a number! There are 5 letters in that word...

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

Enter some text to see if its a number or not: May 30th 2012

May is NOT a number! There are 3 letters in that word...
30th is NOT a number! There are 2 letters in that word...
2012 is a number..

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

Enter some text to see if its a number or not: 5 31 2012

5 is a number..
31 is a number..
2012 is a number..

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.

Looking for sample code for a stack? Click here.

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 – How To Find The Minimum & Maximum Of 3 Numbers, Print In Ascending Order

This page will demonstrate how to find the minimum and maximum of 3 numbers. After the maximum and minimum numbers are obtained, the 3 numbers are displayed to the screen in ascending order.

This program uses multiple if-statements to determine equality, and uses 3 seperate int varables to store its data. This program is very basic, so it does not utilize an integer array, or any sorting methods.

NOTE: If you want to find the Minimum & Maximum of numbers contained in an integer array, click here.


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.

Once compiled, you should get this as your output

Please enter 3 numbers: 89 56 1987
The numbers you just entered are: 89 56 1987

The maximum number is: 1987
The minimum number is: 56
The numbers in order are: 56 89 1987

C++ || Snippet – How To Read & Write Data From A User Specified Text File

This page will consist of a demonstration of a simple quadratic formula program, which highlights the use of the input/output mechanisms of manipulating a text file. This program is very similar to an earlier snippet which was presented on this site, but in this example, the user has the option of choosing which file they want to manipulate. This program also demonstrates how to read in data from a file (numbers), manipulate that data, and output new data into a different text file.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Fstream
Ifstream
Ofstream
Working With Files
C_str() - Convert A String To Char Array Equivalent
Getline - String Version

Note: The data file that is used in this example can be downloaded here.

Also, in order to read in the data .txt file, you need to save the .txt file in the same directory (or folder) as your .cpp file is saved in. If you are using Visual C++, this directory will be located in

Documents > Visual Studio 2010 > Projects > [Your project name] > [Your project name]


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.

Once compiled, you should get this as your output

Please enter the name of the file: INPUT_Quadratic_programmingnotes_freeweq_com.txt

For the numbers
a = 2
b = 4
c = -16

root 1 = 2
root 2 = -4

Press ENTER to continue...