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RSelect method not working as expected

Open JuliaAlves opened this issue 2 years ago • 0 comments

Problem

The RSelect method is not returning the correct k-smallest element.

Here is an example:

arr := []int{5, 2, 6, 8, 3, 1}
x := RSelect(arr, 6, 0)

fmt.Println("Value: ", x)

The printed value is 5, when it should be 1.

Test

The test implemented for RSelect is running successfully, showing that it was implemented incorrectly.

There is an error in the applied boolean logic. The test is using && to validate the returned values, when it should be using ||.

Here is the correct test implementation:

func TestRSelect(t *testing.T) {
	arr := []int{5, 2, 6, 8, 3, 1}

	i0 := RSelect(arr, 6, 0)
	i1 := RSelect(arr, 6, 1)
	i2 := RSelect(arr, 6, 2)
	i3 := RSelect(arr, 6, 3)
	i4 := RSelect(arr, 6, 4)
	i5 := RSelect(arr, 6, 5)
	if i0 != 1 ||
		i1 != 2 ||
		i2 != 3 ||
		i3 != 5 ||
		i4 != 6 ||
		i5 != 8 {
		fmt.Println("Error: ", i0, i1, i2, i3, i4, i5)
		t.Error()
	}
}

JuliaAlves avatar Jun 15 '22 23:06 JuliaAlves