Add: Validate IP Address

Author: openset

problems/validate-ip-address/validate_ip_address.go

@@ -1 +1,15 @@
-package validate_ip_address
+package problem_468
+
+import (
+	"net"
+	"regexp"
+)
+
+func validIPAddress(IP string) string {
+	if p4 := net.ParseIP(IP).To4(); len(p4) == net.IPv4len && p4.String() == IP {
+		return "IPv4"
+	} else if regexp.MustCompile(`^([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}$`).MatchString(IP) {
+		return "IPv6"
+	}
+	return "Neither"
+}

problems/validate-ip-address/validate_ip_address_test.go

@@ -1 +1,47 @@
-package validate_ip_address
+package problem_468
+
+import "testing"
+
+type caseType struct {
+	input    string
+	expected string
+}
+
+func TestValidIPAddress(t *testing.T) {
+	tests := [...]caseType{
+		{
+			input:    "172.16.254.1",
+			expected: "IPv4",
+		},
+		{
+			input:    "172.16.254.01",
+			expected: "Neither",
+		},
+		{
+			input:    "256.256.256.256",
+			expected: "Neither",
+		},
+		{
+			input:    "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+			expected: "IPv6",
+		},
+		{
+			input:    "2001:db8:85a3:0:0:8A2E:0370:7334",
+			expected: "IPv6",
+		},
+		{
+			input:    "2001:0db8:85a3::8A2E:0370:7334",
+			expected: "Neither",
+		},
+		{
+			input:    "02001:0db8:85a3:0000:0000:8a2e:0370:7334",
+			expected: "Neither",
+		},
+	}
+	for _, tc := range tests {
+		output := validIPAddress(tc.input)
+		if output != tc.expected {
+			t.Fatalf("input: %v, output: %v, expected: %v", tc.input, output, tc.expected)
+		}
+	}
+}