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go/isogram/README.md

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+# Isogram
+
+Determine if a word or phrase is an isogram.
+
+An isogram (also known as a "nonpattern word") is a word or phrase without a repeating letter.
+
+Examples of isograms:
+
+- lumberjacks
+- background
+- downstream
+
+The word *isograms*, however, is not an isogram, because the s repeats.
+
+To run the tests simply run the command `go test` in the exercise directory.
+
+If the test suite contains benchmarks, you can run these with the `-bench`
+flag:
+
+    go test -bench .
+
+For more detailed info about the Go track see the [help
+page](http://exercism.io/languages/go).
+
+## Source
+
+Wikipedia [https://en.wikipedia.org/wiki/Isogram](https://en.wikipedia.org/wiki/Isogram)
+
+## Submitting Incomplete Problems
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
+

go/isogram/isogram.go

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+package isogram
+
+import "strings"
+
+const testVersion = 1
+
+func IsIsogram(inp string) bool {
+	used := make(map[rune]int)
+	inp = strings.ToLower(inp)
+	for _, l := range inp {
+		switch l {
+		case '-':
+			continue
+		case ' ':
+			continue
+		}
+		if used[l] > 0 {
+			return false
+		}
+		used[l] = used[l] + 1
+	}
+	return true
+}

go/isogram/isogram_test.go

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+package isogram
+
+import "testing"
+
+var testCases = []struct {
+	word     string
+	expected bool
+}{
+	{"duplicates", true},
+	{"eleven", false},
+	{"subdermatoglyphic", true},
+	{"Alphabet", false},
+	{"thumbscrew-japingly", true},
+	{"Hjelmqvist-Gryb-Zock-Pfund-Wax", true},
+	{"Heizölrückstoßabdämpfung", true},
+	{"the quick brown fox", false},
+	{"Emily Jung Schwartzkopf", true},
+	{"éléphant", false},
+}
+
+func TestIsIsogram(t *testing.T) {
+	for _, c := range testCases {
+		if IsIsogram(c.word) != c.expected {
+			t.Fatalf("FAIL: Word %q, expected %v, got %v", c.word, c.expected, !c.expected)
+		}
+
+		t.Logf("PASS: Word %q", c.word)
+	}
+}
+
+func BenchmarkIsIsogram(b *testing.B) {
+	b.StopTimer()
+	for _, c := range testCases {
+		b.StartTimer()
+
+		for i := 0; i < b.N; i++ {
+			IsIsogram(c.word)
+		}
+
+		b.StopTimer()
+	}
+}
+
+const targetTestVersion = 1
+
+func TestTestVersion(t *testing.T) {
+	if testVersion != targetTestVersion {
+		t.Errorf("Found testVersion = %v, want %v.", testVersion, targetTestVersion)
+	}
+}