From f3712555d5d9c9614366ed1998e8e4c8751674a2 Mon Sep 17 00:00:00 2001
From: Dan Buch <daniel.buch@gmail.com>
Date: Sun, 18 Nov 2012 07:50:09 -0500
Subject: [PATCH] Go Euclid!

---
 algs4/Makefile                              | 20 +++++++++++
 algs4/src/meatballhat.com/algs4-gcd/main.go | 38 +++++++++++++++++++++
 2 files changed, 58 insertions(+)
 create mode 100644 algs4/Makefile
 create mode 100644 algs4/src/meatballhat.com/algs4-gcd/main.go

diff --git a/algs4/Makefile b/algs4/Makefile
new file mode 100644
index 0000000..7df9fa2
--- /dev/null
+++ b/algs4/Makefile
@@ -0,0 +1,20 @@
+CLEAN_GOPATH := $(shell echo $(GOPATH) | tr ":" "\n" | grep -v '^$$' | grep -v $(PWD) | tr "\n" ":")
+GOPATH := $(PWD):$(CLEAN_GOPATH)
+PACKAGES := meatballhat.com/algs4-gcd
+
+test: build
+	go test $(PACKAGES)
+
+build: deps
+	go install $(PACKAGES)
+
+fmt:
+	go fmt $(PACKAGES)
+
+deps:
+	go get $(PACKAGES)
+
+clean:
+	rm -v bin/*
+
+.PHONY: test build clean fmt
diff --git a/algs4/src/meatballhat.com/algs4-gcd/main.go b/algs4/src/meatballhat.com/algs4-gcd/main.go
new file mode 100644
index 0000000..c7fa5f1
--- /dev/null
+++ b/algs4/src/meatballhat.com/algs4-gcd/main.go
@@ -0,0 +1,38 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+const USAGE string = `Usage: algs4-gcd <int> <int>`
+
+func gcd(p, q uint64) uint64 {
+	if q == 0 {
+		return p
+	}
+	r := p % q
+	return gcd(q, r)
+}
+
+func main() {
+	if len(os.Args) < 3 {
+		fmt.Println(USAGE)
+		os.Exit(1)
+	}
+
+	p, err := strconv.ParseUint(os.Args[1], 10, 0)
+	if err != nil {
+		fmt.Println("Wherps: ", err)
+		os.Exit(1)
+	}
+
+	q, err := strconv.ParseUint(os.Args[2], 10, 0)
+	if err != nil {
+		fmt.Println("Wherps: ", err)
+		os.Exit(1)
+	}
+
+	fmt.Println(gcd(p, q))
+}