Machine Input Output Cheat Sheet
31 Oct 2026
Quick answer
A quick revision cheat sheet on machine input-output reasoning for SSC, Banking, Railway and state exams. It covers how a word-and-number machine rearranges items step by step, the common rule types, how to find the hidden rule, how to reach a later step quickly, and the common traps, with a worked example.
Machine Input Output Cheat Sheet
Quick Revision
A machine input-output question shows a "machine" that takes a line of words and numbers and rearranges it, one step at a time, by a hidden rule. Your job is to spot the rule and apply it.
1. Common Rule Types
- Sorting words into alphabetical order, or numbers into ascending/descending order;
- Shifting one item from one end to the other each step;
- Alternating ends — one item moves to the front, the next to the back;
- A mix: one word and one number placed each step.
2. Finding the Rule
Compare the INPUT with Step 1: what moved, and to where?
Compare Step 1 with Step 2: is the same kind of move repeated?The number of steps usually equals the number of items to be placed.
3. Reaching a Later Step
Once the rule is clear you can jump ahead: you do not need to redraw every step. Count how many items are already placed and apply the rule to the rest.
4. Worked Example
Input : cat 24 ox 11 ant
Step 1: ant cat 24 ox 11 (smallest-alphabet word to the front)
Step 2: ant cat ox 24 11 (next word to the front of the unsorted part)The rule is "move the next word in alphabetical order to the front each step".
5. Exam Quick Tips
- Always compare consecutive steps to read the rule, not just input vs output.
- Watch whether words and numbers follow the same rule or separate ones.
- The last step is the fully arranged line — the machine then stops.
Keep revising with the rest of the Reasoning section:
How this was made: Drafted with AI assistance; spot-checked by the editor on 31 October 2026.