= Solution
Return immediately on equality and omit the final <array> inspection:
``
def searchEarly(u: Array[Int], z: Int): Boolean = {
var a = 0
var b = u.length
while (a < b) {
val middle = a + (b - a) / 2
val value = u(middle)
if (value == z) return true
if (value > z) a = middle + 1
else b = middle
}
false
}
``
An equality returns a genuine matching entry. After a nonequal comparison, descending order excludes the inspected middle entry and one whole side. In the half-open range, setting `b = middle` already excludes the middle index; subtracting one would incorrectly exclude another possible entry. The candidate interval decreases as before, so absence is reported exactly when no possible entry remains.
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