Java Loops II

  • + 5 comments
    a += b * (int) Math.pow(2, j);
    

    is shorthand for

    a = a + b * (int) Math.pow(2, j);
    

    Math.pow() is a function that is provided to us by Java. Here, it takes 2 parameters. When I pass in 2 and j, it does exponentiation (known as "power") as 2 to the j-th power. For example, Math.pow(3,5) = 3 * 3 * 3 * 3 * 3.

    Also, Math.pow() returns a double instead of an int. We "cast" it to an integer by putting

    (int)
    

    in front of it. We cast our result since a is an integer type and we can only assign an int type to it.

    Hope this helps.

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