pwc150 solution in go

3 files changed, 131 insertions, 0 deletions

diff --git a/challenge-150/pokgopun/README b/challenge-150/pokgopun/README
new file mode 100644
index 0000000000..33dfd303a4
--- /dev/null
+++ b/challenge-150/pokgopun/README
@@ -0,0 +1 @@
+Solution by PokGoPun
diff --git a/challenge-150/pokgopun/go/ch-1.go b/challenge-150/pokgopun/go/ch-1.go
new file mode 100644
index 0000000000..5ff80669f6
--- /dev/null
+++ b/challenge-150/pokgopun/go/ch-1.go
@@ -0,0 +1,18 @@
+package main
+
+import (
+	"fmt"
+	"os"
+)
+
+func main() {
+	a, b := "1234", "5678"
+	if len(os.Args) > 2 {
+		a, b = os.Args[1], os.Args[2]
+	}
+	fmt.Printf("Input: $a = '%v' $b = '%v'\n", a, b)
+	for len([]rune(b)) < 51 {
+		a, b = b, a+b
+	}
+	fmt.Println("Output:", string([]rune(b)[50]))
+}
diff --git a/challenge-150/pokgopun/go/ch-2.go b/challenge-150/pokgopun/go/ch-2.go
new file mode 100644
index 0000000000..cacbe2cd46
--- /dev/null
+++ b/challenge-150/pokgopun/go/ch-2.go
@@ -0,0 +1,112 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	l := 500
+	if len(os.Args) > 1 {
+		i, err := strconv.Atoi(os.Args[1])
+		if err != nil {
+			log.Fatal(err)
+		}
+		l = i
+	}
+	fmt.Println("The smallest positive square-free integers are")
+	sf := []uint{1}
+	//fmt.Print("\t1")
+	chk, nxt, _ := primeUtil()
+	for i := 2; i <= l; i++ {
+		if chk(i) {
+			sf = append(sf, uint(i))
+			//fmt.Print(", ", i)
+		} else {
+			n := i
+			p := 2
+			seen := 0
+			for {
+				if n%p != 0 {
+					p = nxt(p)
+				} else {
+					if p == seen {
+						break
+					} else {
+						seen = p
+					}
+					n /= p
+					if n == 1 {
+						sf = append(sf, uint(i))
+						//fmt.Print(", ", i)
+						break
+					} else if chk(n) {
+						if n != seen {
+							sf = append(sf, uint(i))
+							//fmt.Print(", ", i)
+						}
+						break
+					}
+				}
+			}
+		}
+
+	}
+	fmt.Println(sf)
+	//fmt.Print("\n")
+}
+
+func primeUtil() (func(i int) bool, func(i int) int, func()) {
+	m := map[int]bool{}
+	return func(i int) bool {
+			is, ok := m[i]
+			if ok {
+				//fmt.Println("### check prime from cache ###")
+				return is
+			} else {
+				if isPrime(i) {
+					m[i] = true
+					return true
+				}
+				m[i] = false
+				return false
+			}
+		}, func(i int) int {
+			for {
+				i++
+				is, ok := m[i]
+				if ok {
+					//fmt.Println("### check next number from cache ###")
+					if is {
+						return i
+					} else {
+						continue
+					}
+				} else {
+					if isPrime(i) {
+						m[i] = true
+						return i
+					}
+					m[i] = false
+				}
+			}
+		}, func() {
+			fmt.Println("=>", m)
+		}
+}
+func isPrime(n int) bool {
+	//fmt.Println("In isPrime")
+	if n <= 3 {
+		return n > 1
+	} else if n%2 == 0 || n%3 == 0 {
+		return false
+	}
+	for i := 5; i*i <= n; i += 6 {
+		if n%i == 0 || n%(i+2) == 0 {
+			return false
+		}
+	}
+	return true
+}