Question

Explain the algorithm to convert infix expression to postfix.

Answer 1

Push “(“onto Stack, and add “)” to the end of X.

Scan X from left to right and repeat Step 3 to 6 for each element of X until the Stack is empty.

If an operand is encountered, add it to Y.

If a left parenthesis is encountered, push it onto Stack.

If an operator is encountered ,then:

Repeatedly pop from Stack and add to Y each operator (on the top of Stack) which has the same precedence as or higher precedence than operator.

Add operator to Stack.

[End of If]

If a right parenthesis is encountered ,then:

Repeatedly pop from Stack and add to Y each operator (on the top of Stack) until a left parenthesis is encountered.

Remove the left Parenthesis.

[End of If]

[End of If]

END.