Postfix Expression Evaluation Problem Statement

Given a postfix expression, your task is to evaluate the expression. The operator will appear in the expression after the operands. The output for each expression should be the result modulo (109+7). Use modular division when necessary.

Example:

Explanation:
Infix expression: A + B * C - D
Postfix expression: A B + C D - *

Input:

The first line contains an integer ‘T’ representing the number of test cases.
Each of the next ‘T’ lines contains one postfix expression.

Output:

For each test case, print the integer result of evaluating the given postfix expression.

Constraints:

  • The first line of input contains an integer ‘T’ such that 1 ≤ T ≤ 100
  • Each postfix expression has a length ‘N’ such that 1 ≤ N ≤ 103
  • The operands in the expression are represented by integers ‘NUM’ such that 1 ≤ NUM ≤ 100
  • Operators include: '*', '/', '+', '-'
  • Operators and operands are separated by a space
  • No brackets are present in the postfix expression

Note:

You do not need to print the expected output; just implement the function.
AnswerBot
4mo

Evaluate postfix expressions by applying operators after operands. Return result modulo (10^9+7).

  • Iterate through each character in the postfix expression

  • If character is an operand, push it onto the st...read more

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