pwc159 solution in go

2 files changed, 168 insertions, 0 deletions

diff --git a/challenge-159/pokgopun/go/ch-1.go b/challenge-159/pokgopun/go/ch-1.go
new file mode 100644
index 0000000000..719d6a8953
--- /dev/null
+++ b/challenge-159/pokgopun/go/ch-1.go
@@ -0,0 +1,44 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	s := argInts()
+	if len(s) == 0 {
+		s = []int{5, 7, 4}
+	}
+	for _, n := range s {
+		fmt.Println("Input: $n =", n)
+		a, b, c, d := 0, 1, 1, n
+		fmt.Printf("Output: %d/%d, %d/%d", a, b, c, d)
+		if n > 1 {
+			for {
+				k := (n + b) / d
+				a, b, c, d = c, d, k*c-a, k*d-b
+				fmt.Printf(", %d/%d", c, d)
+				if c == 1 && d == 1 {
+					break
+				}
+			}
+		}
+		fmt.Printf("\n\n")
+	}
+}
+
+func argInts() (s []int) {
+	if len(os.Args) > 1 {
+		for _, v := range os.Args[1:] {
+			i, err := strconv.Atoi(v)
+			if err != nil {
+				log.Fatal(err)
+			}
+			s = append(s, i)
+		}
+	}
+	return s
+}
diff --git a/challenge-159/pokgopun/go/ch-2.go b/challenge-159/pokgopun/go/ch-2.go
new file mode 100644
index 0000000000..d61f36a7aa
--- /dev/null
+++ b/challenge-159/pokgopun/go/ch-2.go
@@ -0,0 +1,124 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	s := argInts()
+	if len(s) == 0 {
+		s = []int{5, 10, 20}
+	}
+	for _, n := range s {
+		fmt.Println("Input: $n =", n)
+		m := map[int]int{}
+		for _, v := range factor(n) {
+			m[v]++
+		}
+		//fmt.Println(m)
+		o := -1
+		if len(m)%2 == 0 {
+			o = 1
+		}
+		for _, v := range m {
+			if v > 1 {
+				o = 0
+				break
+			}
+		}
+		fmt.Printf("Output: %d\n\n", o)
+	}
+}
+
+func factor(n int) (s []int) {
+	if n > 1 {
+		chk, nxt, _ := primeUtil()
+		p := 2
+		if chk(n) {
+			s = append(s, n)
+		} else {
+			for {
+				if n%p != 0 {
+					p = nxt(p)
+				} else {
+					s = append(s, p)
+					n /= p
+					if n == 1 {
+						break
+					} else if chk(n) {
+						s = append(s, n)
+						break
+					}
+				}
+			}
+		}
+	}
+	return s
+}
+func argInts() (s []int) {
+	if len(os.Args) > 1 {
+		for _, v := range os.Args[1:] {
+			i, err := strconv.Atoi(v)
+			if err != nil {
+				log.Fatal(err)
+			}
+			s = append(s, i)
+		}
+	}
+	return s
+}
+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
+}