From 541cbe1b04d5e804d2cabe879317cff9ae3f5cb4 Mon Sep 17 00:00:00 2001
From: Mohammad S Anwar <mohammad.anwar@yahoo.com>
Date: Tue, 7 Jun 2022 17:54:35 +0100
Subject: - Added guest contributions by Eric Cheung.

---
 challenge-168/eric-cheung/python/ch-1.py | 39 ++++++++++++++++++++++
 challenge-168/eric-cheung/python/ch-2.py | 57 ++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)
 create mode 100755 challenge-168/eric-cheung/python/ch-1.py
 create mode 100755 challenge-168/eric-cheung/python/ch-2.py

diff --git a/challenge-168/eric-cheung/python/ch-1.py b/challenge-168/eric-cheung/python/ch-1.py
new file mode 100755
index 0000000000..df5ae80e8e
--- /dev/null
+++ b/challenge-168/eric-cheung/python/ch-1.py
@@ -0,0 +1,39 @@
+
+## Remarks
+## https://en.wikipedia.org/wiki/Perrin_number
+
+import math
+
+def IsPrime(nInput):
+
+    for nDiv in range(2, int(math.sqrt(nInput)) + 1):
+        if nInput % nDiv == 0:
+            return False
+
+    return True
+
+arrPerrinPrime = []
+arrPerrinNum = []
+
+arrPerrinNum.append(3)
+arrPerrinNum.append(0)
+arrPerrinNum.append(2)
+
+arrPerrinPrime.append(2)
+arrPerrinPrime.append(3)
+
+while len(arrPerrinPrime) < 13:
+    nNuNum = arrPerrinNum[-2] + arrPerrinNum[-3]
+    arrPerrinNum.append(nNuNum)
+
+    if not IsPrime(nNuNum):
+        continue
+
+    nCount = arrPerrinPrime.count(nNuNum)
+
+    if nCount > 0:
+        continue
+
+    arrPerrinPrime.append(nNuNum)
+
+print (arrPerrinPrime)
diff --git a/challenge-168/eric-cheung/python/ch-2.py b/challenge-168/eric-cheung/python/ch-2.py
new file mode 100755
index 0000000000..4bcd6f1e3a
--- /dev/null
+++ b/challenge-168/eric-cheung/python/ch-2.py
@@ -0,0 +1,57 @@
+
+## Remarks
+## https://en.wikipedia.org/wiki/Home_prime
+
+import math
+
+def IsPrime(nInput):
+
+    for nDiv in range(2, int(math.sqrt(nInput)) + 1):
+        if nInput % nDiv == 0:
+            return False
+
+    return True
+
+
+def PrimeFact(nOrigInput):
+
+    nInput = nOrigInput
+    arrPrimeFact = []
+
+    for nDiv in range(2, nOrigInput):
+
+        while nInput % nDiv == 0 and nInput > 0:
+
+            nInput = nInput / nDiv
+            arrPrimeFact.append(nDiv)
+
+        if nInput == 0:
+            break
+
+    return arrPrimeFact
+
+
+def ConcatArray(arrInput):
+
+    strResult = ""
+
+    for arrElem in arrInput:
+        strResult = strResult + str(arrElem)
+
+    return int(strResult)
+
+
+## print (PrimeFact(511))
+## print (ConcatArray(PrimeFact(511)))
+## print (ConcatArray(PrimeFact(8)))
+
+
+nOrigInputNum = 10
+
+nInputNum = nOrigInputNum
+
+while not IsPrime(nInputNum):
+    nInputNum = ConcatArray(PrimeFact(nInputNum))
+
+print ("HP(" + str(nOrigInputNum) + ") = " + str(nInputNum))
+
-- 
cgit