# Basics of INPUT – OUTPUT

Let us first understand, what exactly is meant by Machine Input. This is basically a topic of logical reasoning where a set of words, numbers or their combination is given in a particular sequence in various steps. You need to identify the pattern in which the initial input given to you is processed in various steps and then apply the same pattern to the statement in the questions and answer accordingly.

There may be numerous patterns which may be followed while processing a given input. We will now have a look at the most common patterns that you may encounter in the exams.

### 1. Shifting Pattern –

This is the most common pattern on which most of the questions are based. A particular number or word is shifted from its initial position to usually an extreme end. This shifting may be based on various parameters, for instance in ascending order, descending order, on the basis of vowel/consonant in words or on the basis of odd/even in case of numbers, number of alphabets in the given word etc.

Consider the following example –

Input – 89 bind 32 goal house 61 12 joy
• Step I – 12 89 bind 32 goal house 61 joy
• Step II – 12 joy 89 bind 32 goal house 61
• Step III – 12 joy 32 89 bind goal house 61
• Step IV – 12 joy 32 house 89 bind goal 61
• Step V – 12 joy 32 house 61 89 bind goal
• Step VI – 12 joy 32 house 61 goal 89 bind
Now if you have a look at the above input, you can clearly make out the pattern. Numbers and words are being shifted in alternate steps, numbers in ascending order and alphabets in descending order. In step I, 12 being the smallest number is shifted to the extreme left end while the rest sequence remains same. In step II, joy (alphabet J) being the biggest in the alphabetical order is shifted first. Again in Step III the second smallest number, 32 has been shifted. This process is carried out till all the numbers and alphabets have been arranged in the pattern. Once you have identified the pattern, you can easily arrange the various steps of the input given in question.

Based on the above arrangement, process the given input and answer the number of steps that would be required to complete this arrangement-

Input – 21 victory 11 30 point 64 47 all gone 18 cap

### 2. Double Shifting –

This pattern is same as the shifting pattern, the only difference being, shifting takes place at both the ends of the input. This shifting may take place simultaneously in the same step or in alternate steps, Consider the following example –

Input : more 40 great and 60 74 will
• Step I: 74 more 40 great 60 will and
• Step II: 74 60 more 40 will and great
• Step III: 74 60 40 will and great more
• Step IV: 74 60 40 and great more will

Now, if you observe the above arrangement, you can easily make out the changes at both the ends. 74 being the largest number is shifted to the extreme left end and ‘and’ being the smallest in alphabetical order is shifted to the extreme left end. The shifting at both ends here takes place in a single step.

Things to remember while solving these questions –
• Go through at least first 2-3 steps before deciding the pattern of the sequence. Do go through the last step of the input as well. This will give you some idea of the pattern in which the given output has been processed.
• Make sure that you observe both the ends of the arrangement while identifying the pattern.
• While writing down the different steps of the arrangement, try to use only the first alphabets in case of words in order to save time (Make sure that only a single word is present with the same alphabet when you use this approach). For instance –
• 42 demand earning 64 6 element 9 them output 81 summer 8 power 4 jungle
• Instead of writing each word every time in different steps, you can simply write –
• 42 d ea 64 6 el 9 t o 81 s 8 p 4 j
• Try to label the order/ranking of the number or the alphabet above them in the first step, so that you have a clear idea of the order in which you need to shift them.
• Apart from the common patterns, you may also face patterns based on arithmetic operations on numbers. Exercise caution while you attempt such patterns.
• Make sure that you go through the questions as well before writing down different steps of the input. Proceed till the last step only if it is required in the question.
• Calmly observe the given arrangement. You’ll be able to make out the pattern easily with practice.

Now that you have the basic idea of this topic, try to identify the pattern of the given arrangement.

Input – 52 peak 91 snow freeze 46 cold 15 high 31 73 trek
Step I – 15 52 peak snow freeze 46 cold high 31 73 trek 91
Step II – 15 31 52 peak snow freeze 46 cold high trek 73 91
Step III – 15 31 46 peak snow freeze cold high trek 52 73 91
Step IV – 15 31 46 cold peak snow freeze high trek 52 73 91
Step V – 15 31 46 cold freeze peak snow high trek 52 73 91
Step VI – 15 31 46 cold freeze high peak snow trek 52 73 91

Based on the above arrangement, answer the last step of the following sequence in the comments-

Input – 67 hot sun 19 best 83 ice 49 ace 77 cut 37

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