What is PseudoCode: A Complete Tutorial
Last Updated :
26 Jul, 2025
A Pseudocode is defined as a step-by-step description of an algorithm. Pseudocode does not use any programming language in its representation instead it uses the simple English language text as it is intended for human understanding rather than machine reading.
Pseudocode is the intermediate state between an idea and its implementation(code) in a high-level language.
What is PseudoCode: A Complete TutorialWhat is the need for Pseudocode
Pseudocode is an important part of designing an algorithm, it helps the programmer in planning the solution to the problem as well as the reader in understanding the approach to the problem. Pseudocode is an intermediate state between algorithm and program that plays supports the transition of the algorithm into the program.
Pseudocode is an intermediate state between algorithm and programBefore writing the pseudocode of any algorithm the following points must be kept in mind.
- Organize the sequence of tasks and write the pseudocode accordingly.
- At first, establishes the main goal or the aim. Example:
This program will print first N numbers of Fibonacci series.
- Use standard programming structures such as if-else, for, while, and cases the way we use them in programming. Indent the statements if-else, for, while loops as they are indented in a program, it helps to comprehend the decision control and execution mechanism. It also improves readability to a great extent. Example:
IF "1"
print response
"I AM CASE 1"
IF "2"
print response
"I AM CASE 2"
- Use appropriate naming conventions. The human tendency follows the approach of following what we see. If a programmer goes through a pseudo code, his approach will be the same as per that, so the naming must be simple and distinct.
- Reserved commands or keywords must be represented in capital letters. Example: if you are writing IF…ELSE statements then make sure IF and ELSE be in capital letters.
- Check whether all the sections of a pseudo code are complete, finite, and clear to understand and comprehend. Also, explain everything that is going to happen in the actual code.
- Don't write the pseudocode in a programming language. It is necessary that the pseudocode is simple and easy to understand even for a layman or client, minimizing the use of technical terms.
Good vs Bad ways of writing Pseudocode:
Good Vs Bad way of writing PseudocodePseudocode Examples:
1. Binary search Pseudocode:
Binary search is a searching algorithm that works only for sorted search space. It repeatedly divides the search space into half by using the fact that the search space is sorted and checking if the desired search result will be found in the left or right half.
Example: Given a sorted array Arr[] and a value X, The task is to find the index at which X is present in Arr[].
Below is the pseudocode for Binary search.
BinarySearch(ARR, X, LOW, HIGH)
repeat till LOW = HIGH
MID = (LOW + HIGH)/2
if (X == ARR[mid])
return MID
else if (x > ARR[MID])
LOW = MID + 1
else
HIGH = MID - 1
2. Quick sort Pseudocode:
QuickSort is a Divide and Conquer algorithm. It picks an element as a pivot and partitions the given array around the picked pivot.
Say last element of array is picked as pivot then all elements smaller than pivot element are shifted on the left side of pivot and elements greater than pivot are shifted towards the right of pivot by swapping, the same algorithm is repeatedly followed for the left and right side of pivot until the whole array is sorted.
Below is the pseudocode for Quick sort
QUICKSORT(Arr[], LOW, HIGH) {
if (LOW < HIGH) {
PIVOT = PARTITION(Arr, LOW, HIGH);
QUICKSORT(ARR, LOW, PIVOT – 1);
QUICKSORT(ARR, PIVOT + 1, HIGH);
}
}
Here, LOW is the starting index and HIGH is the ending index.
Algorithm | Pseudocode |
|---|
An Algorithm is used to provide a solution to a particular problem in form of a well-defined step-based form. | A Pseudocode is a step-by-step description of an algorithm in code-like structure using plain English text. |
An algorithm only uses simple English words | Pseudocode also uses reserved keywords like if-else, for, while, etc. |
These are a sequence of steps of a solution to a problem | These are fake codes as the word pseudo means fake, using code like structure and plain English text |
There are no rules to writing algorithms | There are certain rules for writing pseudocode |
Algorithms can be considered pseudocode | Pseudocode cannot be considered an algorithm |
It is difficult to understand and interpret | It is easy to understand and interpret |
Difference between Flowchart and Pseudocode
Flowchart | Pseudocode |
|---|
A Flowchart is pictorial representation of flow of an algorithm. | A Pseudocode is a step-by-step description of an algorithm in code like structure using plain English text. |
A Flowchart uses standard symbols for input, output decisions and start stop statements. Only uses different shapes like box, circle and arrow. | Pseudocode uses reserved keywords like if-else, for, while, etc. |
This is a way of visually representing data, these are nothing but the graphical representation of the algorithm for a better understanding of the code | These are fake codes as the word pseudo means fake, using code like structure but plain English text instead of programming language |
Flowcharts are good for documentation | Pseudocode is better suited for the purpose of understanding |
1. Infosys Pseudocode Questions:
What will be the output of the following pseudocode?
Question 1) for i=0 to 4 step 1 do
If i==i++ + --i then do
display i
end-if
end-for
Answer: 0
Question 2) Set Character c = '7'
switch(c)
case '1': display "One"
case '7': display "Seven"
case '2': display "Two"
default: display "Hello"
break
end-switch
Answer: SevenTwoHello
Question 3) Integer a, p
Set a = 5
a = a + 1
a = a * 2
a = a / 2
p = a / 5 + 6
print p
Answer: 7
Question 4) Integer a, b, c
Set b = 40, a = 20, c = 20
a = a + c
c = c + a
a = a + c
c = c + a
Print a + b + c
Answer: 300
Question 5) Integer a, b, c
Set a = 4, b = 3, c = 1
if (a >> (c - 1) && b << (c + 1))
a = a + c
Else
b = a <<< C
End if
Print a - b + c
Answer: 3
2. Accenture Pseudocode Questions:
What will be the output of the following pseudocode?
Questions 1) What will be the output of the following pseudocode for a = 5, b = 1?
Integer funn(Integer a, Integer b)
if(b + a || a - b) && (b > a) && 1)
a = a+b+b-2
return 3-a
Else
return a-b+1
End if
return a + b
End function fun()
Answer: 5
Questions 2) What will be the output of the following pseudocode for a = 5, b = 1?
Integer funn(Integer a, Integer b)
if((b mod a && a mod b) || (a ^ b > a))
a=a ^ b
Else
return a-b
End if
return a + b
End function funn()
Answer: 5
Questions 3) What will be the output of the following pseudocode?
Integer a, b, c
Set a = 4, b = 4, c = 4
if (a & (b ^ b) & c)
a = a >> 1
End if
Print a + b + c
Answer: 12
Questions 4) What will be the output of the following pseudocode for a = 10, b = 11?
Integer funn(Integer a, Integer b)
if(0)
return a - b - funn(-7, -1)
End if
a = a + a + a + a
return a
End function funn()
Answer: 40
Questions 5) What will be the output of the following pseudocode for a = 5, b = 1?
Integer funn(Integer a, Integer b)
if(b + a || a - b) && (b > a) && 1)
a = a + b + b - 2
return 3 - a
Else
return a - b + 1
End if
return a + b
End function fun()
Answer: 5
3. Capgemini Pseudocode Questions
What will be the output of the following pseudocode?
Question 1) What will be the output of the following pseudocode for a=8, b=1?
Integer funn(Integer a, Integer b)
If(a > b && a > 0)
Return a + b + funn (b-1, a-1)
End if
Return a + b
Answer: 16
Question 2) What will be the output of the following pseudocode for p=7, q=2?
Integer funn(Integer p, Integer q)
if(p + q < 10)
Return 1 + funn(p + 1, q + 1)
Else
Return 2
End if
Answer: 3
Question 3) What will be the output of the following pseudocode for a=2, b=7, c=7?
Integer funn(Integer a, Integer b, Integer c)
if ((b + a) < (a - b))
a = a + c
b = (10 + 10) + c
End if
Return a + b + c
Answer: 16
Question 4) What will be the output of the following pseudocode?
String str1 = "err", str2 = "krr"
Print (count consonant(upper(reverse(str2) + reverse(str1))))
Answer: 5
Question 5) What will be the output of the following pseudo code?
Integer a, b, c
Set a = 2, b = 11, c = 5
if ((4 + 5) < (6 + b))
b = c & a
End if
Print a + b + c
Answer: 7
Conclusion:
In the above discussion, we understood the importance of pseudocode in understanding an algorithm. Pseudocode is a lot simpler to construct and debug as compared to an algorithm.
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