Comparing Two Sorting Methods

Question

This question is similar to ( link ), but not quite what I'm looking for. Here is the selection I wrote below, it is in Java.

public void sort() {

    int smallIndex;

    for(int i = 0; i < arr.length; i++) {

        smallIndex = i;

        for (int j = i + 1; j < arr.length; j++) {
            if (arr[j] < arr[smallIndex]) {

                smallIndex = j;
            }
        }

        if(i < smallIndex)
            swap(i, smallIndex);
    }
}

Here is my swap method.

public void swap(int a, int b) {

    int temp = arr[a];
    arr[a] = arr[b];
    arr[b] = temp;
}

I fill an array with 50,000 random elements between 0 and 999. The method sorts it in order. Each execution is about 1400 milliseconds (1300 - 1500).

Here is a selection from the book I was looking at.

public void sortBook() {

    for(int i = 0; i < arr.length; i++) {

        int minPos = minimumPosition(i);
        swap(minPos, i);
    }
}

Here is a minimal placement method.

public int minimumPosition(int from) {

    int minPos = from;

    for(int i = from + 1; i < arr.length; i++) {

        if(arr[i] < arr[minPos]) {

            minPos = i;
        }
    }

    return minPos;
}

The swap method is the one I use on top. I consistently get about 700 milliseconds of runtime for this with 50,000 elements with a range of 0 - 999.

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Answer 1

, , -

if(i < smallIndex)

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Answer 2

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