master > master: src go - algorithmen + display methoden hinzugefügt

code/golang/internal/algorithms/search/binary/binary.go

@@ -0,0 +1,53 @@
+package binary
+
+/* ---------------------------------------------------------------- *
+ * IMPORTS
+ * ---------------------------------------------------------------- */
+
+import (
+	"fmt"
+
+	"ads/internal/core/logging"
+	"ads/internal/core/metrics"
+)
+
+/* ---------------------------------------------------------------- *
+ * GLOBAL VARIABLES/CONSTANTS
+ * ---------------------------------------------------------------- */
+
+//
+
+/* ---------------------------------------------------------------- *
+ * ALGORITHM binary search
+ * ---------------------------------------------------------------- */
+
+/*
+Inputs: L = Liste von Zahlen, x = Zahl.
+
+Annahme: L sei aufsteigend sortiert.
+
+Outputs: Position von x in L, sonst −1 wenn x nicht in L.
+*/
+func BinarySearch(L []int, x int) int {
+	if len(L) == 0 {
+		logging.LogDebug(fmt.Sprintf("x nicht in L"))
+		return -1
+	}
+	metrics.AddTimeCost()
+	m := int(len(L) / 2)
+	if L[m] == x {
+		logging.LogDebug(fmt.Sprintf("x in Position m gefunden"))
+		return m
+	} else if x < L[m] {
+		logging.LogDebug(fmt.Sprintf("Suche in linker Hälfte fortsetzen."))
+		index := BinarySearch(L[:m], x)
+		return index
+	} else { // } else if x > L[m] {
+		logging.LogDebug(fmt.Sprintf("Suche in rechter Hälfte fortsetzen."))
+		index := BinarySearch(L[m+1:], x)
+		if index >= 0 {
+			index += (m + 1) // NOTE: muss Indexwert kompensieren
+		}
+		return index
+	}
+}

code/golang/internal/algorithms/search/binary/binary_fancy.go

@@ -0,0 +1,94 @@
+package binary
+
+/* ---------------------------------------------------------------- *
+ * IMPORTS
+ * ---------------------------------------------------------------- */
+
+import (
+	"fmt"
+
+	"ads/internal/core/metrics"
+	"ads/internal/core/utils"
+	"ads/internal/setup"
+)
+
+/* ---------------------------------------------------------------- *
+ * GLOBAL VARIABLES/CONSTANTS
+ * ---------------------------------------------------------------- */
+
+//
+
+/* ---------------------------------------------------------------- *
+ * CHECKS
+ * ---------------------------------------------------------------- */
+
+func preChecks(L []int, _ ...interface{}) error {
+	if !utils.IsSortedListInt(L) {
+		return fmt.Errorf("Ungültiger Input: L muss aufsteigend sortiert sein!")
+	}
+	return nil
+}
+
+func postChecks(L []int, x int, index int, _ ...interface{}) error {
+	if utils.ArrayContains(L, x) {
+		if !(index >= 0) {
+			return fmt.Errorf("Der Algorithmus sollte nicht -1 zurückgeben.")
+		}
+		if L[index] != x {
+			return fmt.Errorf("Der Algorithmus hat den falschen Index bestimmt.")
+		}
+	} else {
+		if index != -1 {
+			return fmt.Errorf("Der Algorithmus sollte -1 zurückgeben.")
+		}
+	}
+	return nil
+}
+
+/* ---------------------------------------------------------------- *
+ * ALGORITHM binary search + Display
+ * ---------------------------------------------------------------- */
+
+func FancyBinarySearch(input_L []int, input_x int) (int, error) {
+	var name = "Binärsuchalgorithmus"
+	var inputs = map[string]interface{}{
+		"L": input_L,
+		"x": input_x,
+	}
+	var outputs map[string]interface{}
+	var (
+		output_index int
+	)
+	var err error
+
+	do_once := true
+	for do_once {
+		do_once = false
+		setup.DisplayStartOfAlgorithm(name, inputs)
+		metrics.RestartMetrics()
+
+		// Prechecks:
+		err = preChecks(input_L, input_x)
+		if err != nil {
+			break
+		}
+
+		// Ausführung des Algorithmus:
+		output_index = BinarySearch(input_L, input_x)
+		outputs = map[string]interface{}{
+			"index": output_index,
+		}
+
+		// Letzte Messages:
+		setup.DisplayMetrics()
+		setup.DisplayEndOfAlgorithm(outputs)
+
+		// Postchecks:
+		err = postChecks(input_L, input_x, output_index)
+		if err != nil {
+			break
+		}
+	}
+
+	return output_index, err
+}