diff --git a/src/cmd_initpiv.rs b/src/cmd_initpiv.rs
index f42bddd..501ce13 100644
--- a/src/cmd_initpiv.rs
+++ b/src/cmd_initpiv.rs
@@ -92,7 +92,7 @@ fn get_algorithm_id(public_key_info: &SubjectPublicKeyInfoOwned) -> XResult<Algo
         let rsa_public_key = opt_result!(
             RSAPublicKey::from_der(public_key_info.subject_public_key.raw_bytes()), "Parse public key failed: {}");
         let starts_with_0 = rsa_public_key.1.modulus.starts_with(&[0]);
-        let public_key_bits = (rsa_public_key.1.modulus.len() - if starts_with_0 { 1 } else { 0 }) * 8;
+        let public_key_bits = (rsa_public_key.1.modulus.len() - iff!(starts_with_0, 1, 0)) * 8;
         if public_key_bits == 1024 {
             return Ok(AlgorithmId::Rsa1024);
         }