Challenge 107 (Go)

4 files changed, 69 insertions, 0 deletions

diff --git a/challenge-107/guillermo-ramos/go/ch-1.go b/challenge-107/guillermo-ramos/go/ch-1.go
new file mode 100644
index 0000000000..4a3953c85b
--- /dev/null
+++ b/challenge-107/guillermo-ramos/go/ch-1.go
@@ -0,0 +1,32 @@
+package ch107
+
+import "fmt"
+
+func IsSelfDescriptive(n int) bool {
+	nStr := fmt.Sprint(n)
+
+	digits := make(map[rune]int)
+	for _, r := range nStr {
+		digits[r] += 1
+	}
+
+	for i, r := range nStr {
+		digit := int(r) - '0'
+		appears := digits[rune('0'+i)]
+		if digit != appears {
+			return false
+		}
+	}
+	return true
+}
+
+func SelfDescriptiveNumbers(count int) []int {
+	res := make([]int, 0, count)
+	for i := 0; count > 0; i++ {
+		if IsSelfDescriptive(i) {
+			res = append(res, i)
+			count--
+		}
+	}
+	return res
+}
diff --git a/challenge-107/guillermo-ramos/go/ch107_test.go b/challenge-107/guillermo-ramos/go/ch107_test.go
new file mode 100644
index 0000000000..5ada2e7a2a
--- /dev/null
+++ b/challenge-107/guillermo-ramos/go/ch107_test.go
@@ -0,0 +1,31 @@
+package ch107
+
+import "testing"
+
+func TestIsSelfDescriptive(t *testing.T) {
+	expectedMap := map[int]bool{
+		1210: true,
+		1211: false,
+	}
+	for input, expected := range expectedMap {
+		res := IsSelfDescriptive(input)
+		if res != expected {
+			t.Errorf("IsSelfDescriptive(%d) returned '%v' but '%v' was expected",
+				input, res, expected)
+		}
+	}
+}
+
+func TestSelfDescriptiveNumbers(t *testing.T) {
+	input := 3
+	expected := []int{1210, 2020, 21200}
+	res := SelfDescriptiveNumbers(input)
+	equals := len(expected) == len(res)
+	for i := 0; i < len(res) && equals; i++ {
+		equals = expected[i] == res[i]
+	}
+	if !equals {
+		t.Errorf("SelfDescriptiveNumbers(%d) returned '%v' but '%v' was expected",
+			input, res, expected)
+	}
+}
diff --git a/challenge-107/guillermo-ramos/go/go.mod b/challenge-107/guillermo-ramos/go/go.mod
new file mode 100644
index 0000000000..fb854c7861
--- /dev/null
+++ b/challenge-107/guillermo-ramos/go/go.mod
@@ -0,0 +1,3 @@
+module example.com/ch107
+
+go 1.16
diff --git a/challenge-107/guillermo-ramos/go/run_tests.sh b/challenge-107/guillermo-ramos/go/run_tests.sh
new file mode 100755
index 0000000000..20e7774e09
--- /dev/null
+++ b/challenge-107/guillermo-ramos/go/run_tests.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+go test -v