// Crypto challenge Set1 / Challenge 3
// Decrypt single XOR chiffre

extern crate codec;
extern crate challenge3;

#[cfg(not(test))]
fn main() {
    let args = std::os::args();
    
    if args.len() != 2 {
        println!("USAGE: challenge3 HEX_ENCODED_STRING");
    } else {
        let input = args[1].as_slice();
        match codec::from_hex(input) {
            Err(msg) => println!("Invalid hex string: {}", msg),
            Ok(binary) => {
                let decoded = challenge3::decode_xor(binary.as_slice());
                match std::str::from_utf8(decoded.as_slice()) {
                    Some(result) => println!("Decoded: {}", result),
                    None => println!("Failed to decode to UTF-8 string!")
                }
            }
        }
    }
}

// Crypto challenge Set1 / Challenge 3
// Decrypt single XOR chiffre

extern crate codec;
extern crate challenge3;

#[cfg(not(test))]
fn main() {
    let args = std::os::args();
    
    if args.len() != 2 {
        println!("USAGE: challenge3 HEX_ENCODED_STRING");
    } else {
        let input = args[1].as_slice();
        match codec::from_hex(input) {
            Err(msg) => println!("Invalid hex string: {}", msg),
            Ok(binary) => {
                let result = challenge3::decode_xor(binary.as_slice());
                println!("Text {}", std::str::from_utf8(result.as_slice()));
                println!("Raw {}", result);
            }
        }
    }
}

--- 
+++ 
@@ -15,9 +15,11 @@
         match codec::from_hex(input) {
             Err(msg) => println!("Invalid hex string: {}", msg),
             Ok(binary) => {
-                let result = challenge3::decode_xor(binary.as_slice());
-                println!("Text {}", std::str::from_utf8(result.as_slice()));
-                println!("Raw {}", result);
+                let decoded = challenge3::decode_xor(binary.as_slice());
+                match std::str::from_utf8(decoded.as_slice()) {
+                    Some(result) => println!("Decoded: {}", result),
+                    None => println!("Failed to decode to UTF-8 string!")
+                }
             }
         }
     }
Improve output of Challenge 3
