From ada902ca3d6cf24b4bcea11ff18b1b597d696d83 Mon Sep 17 00:00:00 2001
From: Michael Manring <michael@manring>
Date: Sun, 5 Jun 2022 23:52:14 +0700
Subject: pwc146 solution in go

---
 challenge-146/pokgopun/go/ch-1.go | 51 +++++++++++++++++++++++++++++++++++++++
 challenge-146/pokgopun/go/ch-2.go | 36 +++++++++++++++++++++++++++
 2 files changed, 87 insertions(+)
 create mode 100644 challenge-146/pokgopun/go/ch-1.go
 create mode 100644 challenge-146/pokgopun/go/ch-2.go

diff --git a/challenge-146/pokgopun/go/ch-1.go b/challenge-146/pokgopun/go/ch-1.go
new file mode 100644
index 0000000000..3803018e49
--- /dev/null
+++ b/challenge-146/pokgopun/go/ch-1.go
@@ -0,0 +1,51 @@
+// From https://math.stackexchange.com/questions/1885095/parametrization-of-cardano-triplet
+// a = 3k + 2
+// b^2 * c = (k+1)^2 * (8k + 5)
+package main
+
+import (
+	"fmt"
+	"log"
+	"math"
+	"os"
+	"strconv"
+)
+
+func main() {
+	n := 10001
+	if len(os.Args) > 1 {
+		r, err := strconv.Atoi(os.Args[1])
+		if err != nil {
+			log.Fatal(err)
+		}
+		n = r
+	}
+	for j := 50_000; j <= 1_000_000; j += 50_000 {
+		var k int
+		for i, v := range pmap(uint(j)) {
+			if v {
+				k++
+				if k == n {
+					fmt.Println(i)
+					goto done
+				}
+			}
+		}
+	}
+done:
+}
+func pmap(n uint) []bool {
+	m := make([]bool, int(n)+1)
+	for i := 2; i <= int(n); i++ {
+		m[i] = true
+	}
+	for i := 2; float64(i) <= math.Sqrt(float64(n)); i++ {
+		j := i * i
+		for j <= int(n) {
+			m[j] = false
+			j += i
+		}
+
+	}
+	return m
+}
diff --git a/challenge-146/pokgopun/go/ch-2.go b/challenge-146/pokgopun/go/ch-2.go
new file mode 100644
index 0000000000..b8aea49f0f
--- /dev/null
+++ b/challenge-146/pokgopun/go/ch-2.go
@@ -0,0 +1,36 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+func main() {
+	samples := [][2]uint{
+		[2]uint{3, 5},
+		[2]uint{4, 3},
+	}
+	if len(os.Args) > 1 {
+		var sample [2]uint
+		_, err := fmt.Sscanf(os.Args[1], "%d/%d", &sample[0], &sample[1])
+		if err != nil {
+			log.Fatal(err)
+		}
+		samples = [][2]uint{sample}
+	}
+	for _, v := range samples {
+		p := parent(v)
+		gp := parent(p)
+		fmt.Printf("Input: member = '%d/%d'\nOutput: parent ='%d/%d' and grandparent = '%d/%d'\n", v[0], v[1], p[0], p[1], gp[0], gp[1])
+	}
+}
+
+func parent(s [2]uint) [2]uint {
+	if s[0] > s[1] {
+		return [2]uint{s[0] - s[1], s[1]}
+	} else if s[0] < s[1] {
+		return [2]uint{s[0], s[1] - s[0]}
+	}
+	return [2]uint{1, 1}
+}
-- 
cgit