Fast powering implementation

algorithms/math/FastPowering/fastpowering.go

@@ -0,0 +1,22 @@
+package FastPowering
+
+import (
+	"math"
+)
+
+func fastPowering(base float64, power int) float64 {
+	// Anything raised to the power of zero is 1
+	if power == 0 {
+		return 1
+	}
+
+	// Even powers are redefined via two smaller powers
+	if power%2 == 0 {
+		multiplier := fastPowering(base, power/2)
+		return multiplier * multiplier
+	}
+
+	// Odd powers
+	multiplier := fastPowering(base, int(math.Floor(float64(power/2))))
+	return multiplier * multiplier * base
+}

algorithms/math/FastPowering/fastpowering_test.go

@@ -0,0 +1,21 @@
+package FastPowering
+
+import (
+	"testing"
+)
+
+func TestFastPowering(t *testing.T) {
+	data := []struct {
+		n    float64
+		k    int
+		want float64
+	}{
+		{1, 0, 1}, {2, 2, 4}, {2, 10, 1024}, {3, 3, 27}, {10, 0, 1}, {16, 16, 18446744073709552000},
+	}
+
+	for _, d := range data {
+		if got := fastPowering(d.n, d.k); got != d.want {
+			t.Errorf("Invalid value for N: %f, got: %f, want: %f", d.n, got, d.want)
+		}
+	}
+}