From d1be3105ba259970ebfcf71370fb4baca89abd86 Mon Sep 17 00:00:00 2001
From: Iru Cai <mytbk920423@gmail.com>
Date: Sun, 27 May 2018 14:05:48 +0800
Subject: 72,120

---
 euler72_alt_slow.sh | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100755 euler72_alt_slow.sh

(limited to 'euler72_alt_slow.sh')

diff --git a/euler72_alt_slow.sh b/euler72_alt_slow.sh
new file mode 100755
index 0000000..3a8514e
--- /dev/null
+++ b/euler72_alt_slow.sh
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+euler_phi() {
+	prime_factors=($(factor $1 | cut -d ' ' -f2- | tr ' ' '\n' | sort -u))
+	t=$1
+	for i in ${prime_factors[@]}
+	do
+		t=$(($t/$i*($i-1)))
+	done
+	echo $t
+}
+
+sum=0
+i=2
+while [[ $i -le 1000000 ]]
+do
+	sum=$(($sum+$(euler_phi $i)))
+	i=$(($i+1))
+done
+echo $sum
-- 
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