Introduction: Input Output | Logical Reasoning (LR) and Data Interpretation (DI) - CAT PDF Download

What is Input-Output?

The Input-Output reasoning problems, like computers, are dependent on an Input that is presented in the form of numbers and words. These words or numbers produce an output in a specific format. In which we have to find a special format.
You must first comprehend the logic behind the problems before you can solve them. It is critical that you first grasp the understand the concept and then start solving the questions so that you can determine the end result.

Types of Input Output Reasoning

As now we have a basic idea  of questions related to the Input Output reasoning section. Let us see the various types of questions that you may come across from below. 

1. Single Shifting
In this type of Input Output reasoning, letters or numbers rearrangement will take place from only one end such as either from right end or left end. 

2. Double Shifting
In this type of Input Output reasoning, letters or numbers rearrangement will take place from both ends simultaneously. 

3. Operation Based
In this type of Input Output reasoning, different operations will be performed on words and numbers while rearrangements take place. 

4. Box Based
In this type of Input Output reasoning, numbers will be given and different operations need to be applied on it in each step. 

How to Solve Question Based on Input Output Reasoning- Know all Tips and Tricks

Candidates can find various tips and tricks from below for solving the questions related to the Input Output reasoning section.
Tip # 1: The easiest and fastest way to figure out a pattern is to identify the pattern of arrangement in the last step, and then work backwards to find how the processing is to be done.
Tip # 2: In shifting type input output reasoning the shifting can be various types and can involve various steps, so to conclude, all such steps would not be possible, some examples are given below to have a more clear idea about the type of questions asked in exams. 
Tip # 3: Candidates should look for the patterns given below in sequence to solve the questions related to Input Output reasoning. 

• By arranging the given words in forward or reverse alphabetical order
• By arranging the given numbers in ascending or descending order
• By writing a particular set of words in the reverse order, stepwise 
• By changing places of word/numbers according to a set pattern

Sample Questions

Q: Study the following information carefully and answer the given questions.
A word and number arrangement device when given an input line of words and num- bers rearranges them following a particular pattern in each step. The following is an illustration of input and rearrangement.
Input: expected 20 more funniest 31 42 sea 51 rings 26 79 joyful
Step I: expected funniest 20 more 31 42 sea 51 rings 26 79 joyful
Step II: expected funniest 79 51 20 more 31 42 sea rings 26 joyful
Step III: expected funniest 79 51 joyful more 20 31 42 sea rings 26
Step IV: expected funniest 79 51 joyful more 42 31 20 sea rings 26
Step V: expected funniest 79 51 joyful more 42 31 rings sea 20 26
Step VI: expected funniest 79 51 joyful more 42 31 rings sea 26 20
And Step VI is the last step of the above input, as the desired arrangement is obtained.
As per the hides followed in the above steps, find out in each of the following questions the appropriate step for the given input.
Input: blood 21 all 25 my 57 91 equals 59 strengthens 24 and
How many elements are there between 25 and 24 in step V?
Sol: In the given illustration:
In Step I, Two words were picked and arranged in alphabetical order and were finally placed at the left corner
In Step II, Two numbers were picked and arranged in descending order next to words and so on.
Before answering any of the questions, first we will solve the Input String that will help us to solve questions much more easily and much faster.
Input: blood 21 all 25 my 57 91 equals 59 strengthens 24 and
Step I: all and blood 21 25 my 57 91 equals 59 strengthens 24
Step II: all and 91 59 blood 21 25 my 57 equals strengthens 24
Step III: all and 91 59 blood equals 21 25 my 57 strengthens 24
Step IV: all and 91 59 blood equals 57 25 21 my strengthens 24
Step V: all and 91 59 blood equals 57 25 my strengthens 21 24
Step VI: all and 91 59 blood equals 57 25 my strengthens 24 21 
Hence, in this illustration Step VI is the final step. 
There are 3 elements between 24 and 25.

Q2: Study the following information carefully and answer the given questions.
A Machine arranges the given input in the following way.
Input: 18 Quickly Teacher Pacer 40 28 86 Heaven
Step 1: Heave Quickl Teache Pace 40 28 86 18
Step 2: Heave 18 Quickl Teache Pace 40 28 86
Step 3: Heav 18 Pac 28 Quick Teach 40 86
Step 4: Hea 18 Pa 28 Teac 40 Quic 86
Step 5: He 18 P 28 Tea 40 Qui 86
And Step 5 is the last step of the above input.
As per the pattern followed in the above steps, find out in each of the following ques- tions the appropriate step for the given input.
Input: 20 Quicker towel Parker 41 29 87 Harness
Which of the following is second to the right of the one that is 4th from the right end in Step IV?
Sol: In the given illustration:
In step 1, we arrange the smallest word as per alphabetical order in the left end and the smallest number in the right end. All the words are written with one letter being removed.
From the second step, we arrange the smallest word as per alphabetical order and the smallest number from left to right with one letter being removed from every word till the end. A word and number are arranged simultaneously in each step.
Note: In the second step, there will be no removal of words. Now given input is:
Input: 20 Quicker towel Parker 41 29 87 Harness
Step 1: Harnes Quicke Towe Parke 41 29 87 20
Step 2: Harnes 20 Quicke Towe Parke 41 29 87
Step 3: Harne 20 Park 29 Quick Tow 41 87
Step 4: Harn 20 Par 29 Quic 41 To 87
Step 5: Har 20 Pa 29 Qui 41 T 87
Fourth from the right end in Step IV is ‘Quic’ and second to the right of ‘Quic’ is ‘To’.
Hence, ‘To’ is the right answer.