Euler 12 Done.

src/main/go/src/Euler12.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"fmt"
+	"mathlib"
+	//"time"
+)
+
+func main() {
+	done := false
+	factorCount := 0
+	maxFactor := 0
+	i := 1
+	for !done {
+		factors := mathlib.AllFactors(generateTriangleNumber(i))
+		factorCount = len(factors)
+		if factorCount > maxFactor {
+			maxFactor = factorCount
+		}
+		if factorCount > 500 {
+			done = true
+		} else {
+			if i%1000 == 0 {
+				fmt.Println("F: ",i, len(factors), maxFactor)
+			}
+			i++
+		}
+	}
+
+	fmt.Printf("The %v triangle number has > 500 factors and has a value of %v \n",i,generateTriangleNumber(i))
+}
+
+func generateTriangleNumber(base int) int {
+	triangleNumber := 0
+	for i:=1; i<=base;i++{
+		triangleNumber += i
+	}
+	return triangleNumber
+}
+

src/main/go/src/mathlib/mathlib.go

@@ -3,7 +3,6 @@ package mathlib
 import (
 	"math"
 //	"strconv"
-//		"fmt"
 	"time"
 	"fmt"
 )
@@ -33,13 +32,19 @@ func IsPrime(number int) (bool) {
 func AllFactors (number int) ([]int) {
 	var factors []int
 
-	sqrt := int( math.Sqrt( float64(number) ) )
+	sqrt := int(math.Ceil(math.Sqrt(float64(number))))
+
+	factors = append(factors, 1) //Per def 1 is a prime factor of whatever number.
 
 	for i := 2 ; i <= sqrt ; i++ {
 		if ( math.Mod(float64(number), float64(i)) < 0.00001) {
 			factors = append(factors, i)
+			factors = append(factors, (number/i))
 		}
 	}
+	factors = append(factors, number) //Per def number is a prime factor of  number.
+	//TODO: Remove duplicates
+
 	return factors
 }
 
@@ -94,6 +99,14 @@ func IsPytagoreanTriplet(a int, b int, c int) bool {
 	return (aSquared + bSquared == cSquared)
 }
 
+func GenerateTriangleNumber(base int) int {
+	triangleNumber := 0
+	for i:=1; i<=base;i++{
+		triangleNumber += i
+	}
+	return triangleNumber
+}
+
 func Sieve(size int) []int {
 	base := time.Now()
 	//create a slice of ints

src/main/go/src/mathlib/mathlib_test.go

@@ -2,7 +2,7 @@ package mathlib
 
 import (
 	"testing"
-//	"fmt"
+	//"fmt"
 )
 
 func TestIsPrime(t *testing.T) {
@@ -63,7 +63,23 @@ func TestSieve(t *testing.T){
 	if (len(primes) == 1) {
 		t.Errorf("Error")
 	}
+}
+
+func TestAllFactors(t *testing.T) {
+	aTriangleNumber := GenerateTriangleNumber(12375)
+	allFactorsForThat := AllFactors(aTriangleNumber)
+
+	if (len(allFactorsForThat) != 576) {
+		t.Errorf("Error: Allfactors says number of factors is %v while it should be 576",len(allFactorsForThat))
+	}
+}
+func TestAllFactors2(t *testing.T) {
+	aTriangleNumber := GenerateTriangleNumber(7)
+	allFactorsForThat := AllFactors(aTriangleNumber)
 
+	if (len(allFactorsForThat) != 6) {
+		t.Errorf("Error: Allfactors says number of factors is %v while it should be 6",len(allFactorsForThat))
+	}
 }