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* fixup! Format Python code with psf/black push * Create codespell.yml * fixup! Format Python code with psf/black push
71 lines
2.0 KiB
Python
71 lines
2.0 KiB
Python
"""
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Output:
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Enter a Postfix Equation (space separated) = 5 6 9 * +
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Symbol | Action | Stack
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-----------------------------------
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5 | push(5) | 5
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6 | push(6) | 5,6
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9 | push(9) | 5,6,9
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| pop(9) | 5,6
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| pop(6) | 5
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* | push(6*9) | 5,54
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| pop(54) | 5
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| pop(5) |
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+ | push(5+54) | 59
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Result = 59
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"""
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import operator as op
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def Solve(Postfix):
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Stack = []
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Div = lambda x, y: int(x / y) # integer division operation
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Opr = {
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"^": op.pow,
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"*": op.mul,
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"/": Div,
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"+": op.add,
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"-": op.sub,
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} # operators & their respective operation
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# print table header
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print("Symbol".center(8), "Action".center(12), "Stack", sep=" | ")
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print("-" * (30 + len(Postfix)))
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for x in Postfix:
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if x.isdigit(): # if x in digit
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Stack.append(x) # append x to stack
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print(
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x.rjust(8), ("push(" + x + ")").ljust(12), ",".join(Stack), sep=" | "
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) # output in tabular format
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else:
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B = Stack.pop() # pop stack
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print(
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"".rjust(8), ("pop(" + B + ")").ljust(12), ",".join(Stack), sep=" | "
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) # output in tabular format
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A = Stack.pop() # pop stack
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print(
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"".rjust(8), ("pop(" + A + ")").ljust(12), ",".join(Stack), sep=" | "
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) # output in tabular format
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Stack.append(
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str(Opr[x](int(A), int(B)))
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) # evaluate the 2 values popped from stack & push result to stack
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print(
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x.rjust(8),
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("push(" + A + x + B + ")").ljust(12),
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",".join(Stack),
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sep=" | ",
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) # output in tabular format
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return int(Stack[0])
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if __name__ == "__main__":
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Postfix = input("\n\nEnter a Postfix Equation (space separated) = ").split(" ")
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print("\n\tResult = ", Solve(Postfix))
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