1 files changed, 43 insertions, 0 deletions
diff --git a/src/solvers/Challenge8.scala b/src/solvers/Challenge8.scala
new file mode 100644
index 0000000..5247075
--- /dev/null
+++ b/src/solvers/Challenge8.scala
@@ -0,0 +1,43 @@
+package ixee.cryptopals.solvers
+
+import scala.io.Source
+import ixee.cryptopals.utils.ByteUtils._
+import ixee.cryptopals.utils.StreamUtils._
+import ixee.cryptopals.utils.ConversionUtils._
+import ixee.cryptopals.utils.FunctionUtils._
+import ixee.cryptopals.utils._
+import io.github.marklister.base64.Base64._
+import javax.crypto.Cipher
+import javax.crypto.spec.SecretKeySpec
+
+object Challenge8 {
+  val path = "./data/8.txt"
+
+  lazy val ciphertext =
+    Source
+      .fromFile(path)
+      .getLines()
+      .toSeq
+      .map(hexStr2Bytes)
+      //.mkString
+      //.toByteArray
+
+  def run = {
+    ciphertext
+      .zipWithIndex
+      .map(x => (x._1.grouped(16).toStream, x._2 + 1)) // 
+      // this might be decent, line #133 is #2 under this metric
+      // .map(x => (avgHammingDistance(x._1), x._2)).sortBy(_._1)
+      /*
+       * but looking for actual duplicate data is better:
+       * line 133 is #1 with six duplicate blocks,
+       * old #1 of 177 has 0 duplicate blocks.
+       */
+      .map(x => (dupBlocks(x._1), x._2)).sortBy(_._1 * -1)
+      .head
+      ._2
+  }
+
+  def dupBlocks(xs: Seq[Seq[Byte]]) =
+    pairsOf(xs).map(tup(_ == _)).count(_ == true)
+}