- 2070 Magh · 4+1 marks
Convert and evaluate A+(B*C-(D/E^F)*G)*H
Short answer
Postfix: ABC*DEF^/G*-H*+. Evaluating with A=2, B=3, C=4, D=8, E=2, F=3, G=5, H=2 yields 16.
Convert the following infix expression into postfix and also evaluate it: A+(B*C-(D/E^F)*G)*H
Conversion of A + (B * C − (D / E ^ F) * G) * H
^ has the highest precedence and is right-associative; then * /; then + -.
| Step | Symbol | Stack (bottom → top) | Postfix output |
|---|---|---|---|
| 1 | A | (empty) | A |
| 2 | + | + | A |
| 3 | ( | +( | A |
| 4 | B | +( | AB |
| 5 | * | +(* | AB |
| 6 | C | +(* | ABC |
| 7 | - | +(- | ABC* |
| 8 | ( | +(-( | ABC* |
| 9 | D | +(-( | ABC*D |
| 10 | / | +(-(/ | ABC*D |
| 11 | E | +(-(/ | ABC*DE |
| 12 | ^ | +(-(/^ | ABC*DE |
| 13 | F | +(-(/^ | ABC*DEF |
| 14 | ) | +(- | ABC*DEF^/ |
| 15 | * | +(-* | ABC*DEF^/ |
| 16 | G | +(-* | ABC*DEF^/G |
| 17 | ) | + | ABC*DEF^/G*- |
| 18 | * | +* | ABC*DEF^/G*- |
| 19 | H | +* | ABC*DEF^/G*-H |
| end | (pop all) | (empty) | ABC*DEF^/G*-H*+ |
Postfix: ABC*DEF^/G*-H*+
Evaluation
No values are given, so assume A = 2, B = 3, C = 4, D = 8, E = 2, F = 3, G = 5, H = 2. Operands are pushed; an operator pops the right operand first, then the left.
| Step | Symbol | Action | Stack (bottom → top) |
|---|---|---|---|
| 1 | A | push 2 | 2 |
| 2 | B | push 3 | 2, 3 |
| 3 | C | push 4 | 2, 3, 4 |
| 4 | * | pop 4 (right), 3 (left); 3 * 4 = 12; push | 2, 12 |
| 5 | D | push 8 | 2, 12, 8 |
| 6 | E | push 2 | 2, 12, 8, 2 |
| 7 | F | push 3 | 2, 12, 8, 2, 3 |
| 8 | ^ | pop 3 (right), 2 (left); 2 ^ 3 = 8; push | 2, 12, 8, 8 |
| 9 | / | pop 8 (right), 8 (left); 8 / 8 = 1; push | 2, 12, 1 |
| 10 | G | push 5 | 2, 12, 1, 5 |
| 11 | * | pop 5 (right), 1 (left); 1 * 5 = 5; push | 2, 12, 5 |
| 12 | - | pop 5 (right), 12 (left); 12 - 5 = 7; push | 2, 7 |
| 13 | H | push 2 | 2, 7, 2 |
| 14 | * | pop 2 (right), 7 (left); 7 * 2 = 14; push | 2, 14 |
| 15 | + | pop 14 (right), 2 (left); 2 + 14 = 16; push | 16 |
Answer: 16 for the assumed values. Check in infix: E^F = 8, D/8 = 1, 1 × G = 5, B × C = 12, 12 − 5 = 7, 7 × H = 14, A + 14 = 16.
✓ Answer checked by Claude Opus 5.5 (high effort)
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