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3.4: Alternative Execution

  • Page ID
    8554
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    A second form of the if statement is alternative execution, in which there are two possibilities and the condition determines which one gets executed. The syntax looks like this:

    if x%2 == 0 :
        print('x is even')
    else :
        print('x is odd')

    If the remainder when x is divided by 2 is 0, then we know that x is even, and the program displays a message to that effect. If the condition is false, the second set of statements is executed.

    If-Then-Else Logic

    If-Then-Else Logic

    Since the condition must either be true or false, exactly one of the alternatives will be executed. The alternatives are called branches, because they are branches in the flow of execution.


    This page titled 3.4: Alternative Execution is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Chuck Severance.

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