Combine AoC Repos

2016/day07/main.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"regexp"
+	"strings"
+)
+
+func main() {
+	ips := stdinToStringSlice()
+	var allowTLS []string
+	var allowSSL []string
+	for _, ip := range ips {
+		if hasTLS(ip) {
+			allowTLS = append(allowTLS, ip)
+		}
+		if hasSSL(ip) {
+			allowSSL = append(allowSSL, ip)
+		}
+	}
+	fmt.Println("IPs supporting TLS: ", len(allowTLS))
+	fmt.Println("IPs supporting SSL: ", len(allowSSL))
+}
+
+func hasTLS(ip string) bool {
+	bad := false
+	hprSq := getHypernetSqns(ip)
+	for _, hpr := range hprSq {
+		if hasABBA(hpr) {
+			return false
+		}
+	}
+	if !bad && hasABBA(ip) {
+		return true
+	}
+	return false
+}
+
+func hasSSL(ip string) bool {
+	hprSq := getHypernetSqns(ip)
+	rest := cutHypernetSqns(ip, hprSq)
+	for i := range rest {
+		if len(rest) > i+2 {
+			if rest[i] == rest[i+2] && rest[i] != rest[i+1] {
+				bab := string(rest[i+1]) + string(rest[i]) + string(rest[i+1])
+				for j := range hprSq {
+					if strings.Contains(hprSq[j], bab) {
+						return true
+					}
+				}
+			}
+		}
+	}
+	return false
+}
+
+func getHypernetSqns(ip string) []string {
+	var ret []string
+	re := regexp.MustCompile(`\[[^\[]*\]`)
+	s := re.FindAll([]byte(ip), -1)
+
+	for i := range s {
+		ret = append(ret, string(s[i][1:len(s[i])-1]))
+	}
+	return ret
+}
+
+func cutHypernetSqns(ip string, hpn []string) string {
+	for i := range hpn {
+		ip = strings.Replace(ip, hpn[i], "", -1)
+	}
+	return ip
+}
+
+func hasABBA(ip string) bool {
+	for j := range ip {
+		if len(ip) > j+3 {
+			if ip[j] == ip[j+3] && ip[j+1] == ip[j+2] && ip[j] != ip[j+1] {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func stdinToStringSlice() []string {
+	var input []string
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		input = append(input, scanner.Text())
+	}
+	return input
+}