searching algo: binary search

algorithms/searching/binary_search.go

@@ -0,0 +1,23 @@
+package bs
+
+import ()
+
+func search(sortedArray []int, el int) int {
+	init, end := 0, len(sortedArray)-1
+
+	for init <= end {
+		middle := ((end - init) >> 1) + init
+
+		if sortedArray[middle] == el {
+			return middle
+		}
+
+		if sortedArray[middle] < el {
+			init = middle + 1
+		} else {
+			end = middle - 1
+		}
+	}
+
+	return -1
+}

algorithms/searching/binary_search_test.go

@@ -0,0 +1,27 @@
+package bs
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestSearch(t *testing.T) {
+	sorted := make([]int, 10000)
+
+	for i := 0; i < 10000; i++ {
+		sorted[i] = 2 * i
+	}
+
+	for i := 0; i < 10000; i++ {
+		index := search(sorted, 2*i)
+
+		if index != i {
+			fmt.Println(index)
+			t.Error()
+		}
+	}
+
+	if search(sorted, 3) != -1 {
+		t.Error()
+	}
+}