AMU 2026 — Computer PYQ

To convert an infix expression to a postfix expression manually, we follow the operator precedence rules (Parentheses > Multiplication/Division > Addition/Subtraction). For operators with the same precedence level, we apply them from left to right (Left-to-Right Associativity).

Given Expression:

$$A+(B<em>C-D/E</em>G)\ast H$$

1. Step 1: Simplify the innermost parenthesized expression Inside the parentheses $(B<em>C-D/E</em>G)$, we have multiplication ($\ast$), subtraction ($-$), division ($/$), and multiplication ($\ast$).

   • Evaluate the first multiplication from the left ($B\ast C$):

     $$(BC\ast )$$

   • Evaluate the division next ($D/E$):

     $$(DE/)$$

   Now substitute these sub-expressions back into the parentheses:

   $$((BC\ast )-(DE/)\ast G)$$

2. Step 2: Complete the operations inside the parentheses Between subtraction and multiplication, multiplication has higher precedence. So evaluate $(DE/)</em>G$:

   $$(DE/G\ast )$$

   Now the parentheses look like:

   $$((BC\ast )-(DE/G\ast ))$$

   • Finally, resolve the subtraction ($-$) operator inside the parentheses:

     $$(BC\ast DE/G\ast -)$$

3. Step 3: Resolve the remaining expression outside the brackets Now substitute the parenthesized block back into the main expression:

   $$A+(BC\ast DE/G\ast -)\ast H$$

   • We have an addition ($+$) and a multiplication ($\ast$). Multiplication takes higher precedence, so evaluate the block multiplied by $H$:

     $$(BC\ast DE/G\ast -)<em>H⟹(BC</em>DE/G\ast -H\ast )$$

4. Step 4: Perform the final addition Now combine $A$ with the remaining block using the addition ($+$) operator:

   $$A+(BC\ast DE/G\ast -H\ast )⟹ABCDE/-\ast G\ast H\ast +$$

Conclusion:

The resulting string is $ABCDE/-GH+$*, which perfectly matches option (b).