46 lines
1.1 KiB
Markdown
46 lines
1.1 KiB
Markdown
# Evaluate the postfix expression `6 2 3 + -.`
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### **Postfix Evaluation Rules**
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1. Operands are pushed onto a stack.
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2. Operators pop the required number of operands from the stack, perform the operation, and push the result back onto the stack.
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3. Continue until the expression is fully evaluated, and the final value is the only element on the stack.
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---
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### **Step-by-Step Evaluation**
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**Expression**: `6 2 3 + -`
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1. **Read `6`**:
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- Push `6` onto the stack.
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- **Stack**: `[6]`
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2. **Read `2`**:
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- Push `2` onto the stack.
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- **Stack**: `[6, 2]`
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3. **Read `3`**:
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- Push `3` onto the stack.
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- **Stack**: `[6, 2, 3]`
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4. **Read `+`**:
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- Pop the top two operands (`3` and `2`).
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- Perform `2 + 3 = 5`.
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- Push the result (`5`) onto the stack.
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- **Stack**: `[6, 5]`
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5. **Read `-`**:
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- Pop the top two operands (`5` and `6`).
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- Perform `6 - 5 = 1`.
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- Push the result (`1`) onto the stack.
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- **Stack**: `[1]`
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---
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### **Final Result**:
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The result of the postfix expression `6 2 3 + -` is **`1`**.
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