diff --git a/src/aes.rs b/src/aes.rs
index 50e4411..a114d44 100644
--- a/src/aes.rs
+++ b/src/aes.rs
@@ -279,19 +279,6 @@ impl Aes {
         result
     }
 
-    pub fn encrypt_string(&self, text: &String) -> [u8; 16] {
-        let mut block = [0u8; 16];
-        let bytes = text.as_bytes();
-        if bytes.len() > 16 {
-            println!("string too long, will be cut.")
-        }
-        let len = bytes.len().min(16);
-
-        block[..len].copy_from_slice(&bytes[..len]);
-
-        self.encrypt_block(&block)
-    }
-
     pub fn decrypt_block(&self, block: &[u8; 16]) -> [u8; 16] {
         let mut result = [0u8; 16];
 
@@ -328,19 +315,6 @@ impl Aes {
         result
     }
 
-    pub fn decrypt_string(&self, text: &String) -> [u8; 16] {
-        let mut block = [0u8; 16];
-        let bytes = text.as_bytes();
-        if bytes.len() > 16 {
-            println!("string too long, will be cut.")
-        }
-        let len = bytes.len().min(16);
-
-        block[..len].copy_from_slice(&bytes[..len]);
-
-        self.decrypt_block(&block)
-    }
-
     pub fn key_schedule(key_bytes: &[u8; 16]) -> [[u8; 4]; 44] {
         let mut original_key = [[0u8; 4]; 4];
         let mut expanded_key = [[0u8; 4]; 44];
diff --git a/src/main.rs b/src/main.rs
index 8458a52..c3d2864 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -62,26 +62,23 @@ fn main() -> std::io::Result<()> {
             decrypt,
         } => {
             println!("original text: {}", &text);
-            let aeskey: [u8; 16];
             let result: [u8; 16];
-            let aestext: [u8; 16];
             let mut aesnturn: usize = 10;
 
-            match hexkey {
-                false => aeskey = utils::parse_hex_string(&key),
-                true => aeskey = utils::string_to_u8_16(&key),
-            }
-            match nturn {
-                Some(number) => aesnturn = number.parse::<usize>().unwrap(),
-                _ => {}
+            let aeskey: [u8; 16] = match hexkey {
+                false => utils::parse_hex_string(key),
+                true => utils::string_to_u8_16(key),
+            };
+            if let Some(number) = nturn {
+                aesnturn = number.parse::<usize>().unwrap()
             }
 
             let aescipher = Aes::new(&aeskey, &aesnturn);
 
-            match hextext {
-                true => aestext = utils::parse_hex_string(&text),
-                false => aestext = utils::string_to_u8_16(&text),
-            }
+            let aestext: [u8; 16] = match hextext {
+                true => utils::parse_hex_string(text),
+                false => utils::string_to_u8_16(text),
+            };
 
             match decrypt {
                 true => {
@@ -97,11 +94,10 @@ fn main() -> std::io::Result<()> {
             println!();
         }
         Commands::Findkey { key, hexkey } => {
-            let aeskey: [u8; 16];
-            match hexkey {
-                false => aeskey = utils::parse_hex_string(&key),
-                true => aeskey = utils::string_to_u8_16(&key),
-            }
+            let aeskey: [u8; 16] = match hexkey {
+                false => utils::parse_hex_string(key),
+                true => utils::string_to_u8_16(key),
+            };
             let keyfound: [u8; 16] = Aes::findkey(&aeskey);
             if keyfound == aeskey {
                 println!("key found.");
diff --git a/src/square.rs b/src/square.rs
index 0784517..de9725f 100644
--- a/src/square.rs
+++ b/src/square.rs
@@ -47,25 +47,27 @@ impl Aes {
         }
         ciphertexts
     }
-    pub fn decrypt_block_reduced_1_step(&self, block: &[u8; 16]) -> [u8; 16] {
-        let mut result = [0u8; 16];
 
-        let mut state = [[0u8; 4]; 4];
-        for i in 0..16 {
-            state[i % 4][i / 4] = block[i];
-        }
-        add_round_key(&mut state, &clone_into_array(&self.expanded_key[16..20]));
-        inverse_shift_rows(&mut state);
-        inverse_substitute_state(&mut state);
+    // pub fn decrypt_block_reduced_1_step(&self, block: &[u8; 16]) -> [u8; 16] {
+    //     let mut result = [0u8; 16];
+    //
+    //     let mut state = [[0u8; 4]; 4];
+    //     for i in 0..16 {
+    //         state[i % 4][i / 4] = block[i];
+    //     }
+    //     add_round_key(&mut state, &clone_into_array(&self.expanded_key[16..20]));
+    //     inverse_shift_rows(&mut state);
+    //     inverse_substitute_state(&mut state);
+    //
+    //     for i in 0..4 {
+    //         for j in 0..4 {
+    //             result[4 * j + i] = state[i][j]
+    //         }
+    //     }
+    //
+    //     result
+    // }
 
-        for i in 0..4 {
-            for j in 0..4 {
-                result[4 * j + i] = state[i][j]
-            }
-        }
-
-        result
-    }
     pub fn guessroundkey(&texts: &[[u8; 16]; 256]) -> [Vec<u8>; 16] {
         let mut key: [Vec<u8>; 16] = Default::default();
         let mut s: u8;
diff --git a/src/utils.rs b/src/utils.rs
index 75072dd..e3771bd 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -25,8 +25,22 @@ pub fn string_to_u8_16(input: &String) -> [u8; 16] {
     result
 }
 
-pub fn u8_16_to_string(input: &[u8; 16]) -> String {
-    let slice = &input[..];
-    let string = str::from_utf8(slice).expect("Invalid UTF-8");
-    string.to_string()
+// pub fn u8_16_to_string(input: &[u8; 16]) -> String {
+//     let slice = &input[..];
+//     let string = str::from_utf8(slice).expect("Invalid UTF-8");
+//     string.to_string()
+// }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn parse_hex_string_test() {
+        let result: [u8; 16] = parse_hex_string(&String::from("2b7e151628aed2a6abf7158809cf4f3c"));
+        let expected: [u8; 16] = [
+            0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf,
+            0x4f, 0x3c,
+        ];
+        assert_eq!(result, expected);
+    }
 }