if we disallow control characters, we get much more reasonable results

3 files changed, 4 insertions, 1 deletions

diff --git a/data/6.out.txt b/data/6.out.txt
index cd20bce..14283df 100644
--- a/data/6.out.txt
+++ b/data/6.out.txt
diff --git a/src/lib.rs b/src/lib.rs
index e7f695d..9506289 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -191,6 +191,9 @@ fn crack_single_byte_xor_with_confidence (input: &[u8]) -> (u8, f64) {
         if !decrypted.is_ascii() {
             continue;
         }
+        if decrypted.iter().any(|&c| c != b'\n' && (c < 0x20 || c > 0x7E)) {
+            continue;
+        }
         let lowercase = decrypted.to_ascii_lowercase();
         let mut frequencies = [0; 26];
         let mut total_frequency = 0;
diff --git a/tests/lib.rs b/tests/lib.rs
index ac13fb2..b537bd0 100644
--- a/tests/lib.rs
+++ b/tests/lib.rs
@@ -36,7 +36,7 @@ fn problem_4 () {
         .lines()
         .map(|line| line.unwrap().from_hex().unwrap())
         .collect::<Vec<Vec<u8>>>();
-    assert_eq!(matasano::find_single_byte_xor_encrypted_string(&possibles[..]), b"nOW\0THAT\0THE\0PARTY\0IS\0JUMPING*");
+    assert_eq!(matasano::find_single_byte_xor_encrypted_string(&possibles[..]), b"Now that the party is jumping\n");
 }
 
 #[test]