diff --git a/keygen/src/keygen.rs b/keygen/src/keygen.rs
index 83c0f80fa0..b223206f88 100644
--- a/keygen/src/keygen.rs
+++ b/keygen/src/keygen.rs
@@ -78,15 +78,10 @@ fn grind_validator_starts_with(v: String) -> Result<(), String> {
         return Err(String::from("Expected : between PREFIX and COUNT"));
     }
     let args: Vec<&str> = v.split(':').collect();
-    let s = bs58::decode(&args[0]).into_vec()
-    .map(|_| ())
-    .map_err(|err| format!("{}: {:?}", args[0], err));
-    if s.is_err() {
-        return s;
-    }
+    bs58::decode(&args[0]).into_vec().map_err(|err| format!("{}: {:?}", args[0], err))?;
     let count = args[1].parse::<u64>();
     if count.is_err() || count.unwrap() == 0 {
-        return Err(String::from("Expected COUNT to be of type u32"));
+        return Err(String::from("Expected COUNT to be of type u64"));
     }
     Ok(())
 }
@@ -96,15 +91,10 @@ fn grind_validator_ends_with(v: String) -> Result<(), String> {
         return Err(String::from("Expected : between SUFFIX and COUNT"));
     }
     let args: Vec<&str> = v.split(':').collect();
-    let s = bs58::decode(&args[0]).into_vec()
-    .map(|_| ())
-    .map_err(|err| format!("{}: {:?}", args[0], err));
-    if s.is_err() {
-        return s;
-    }
+    bs58::decode(&args[0]).into_vec().map_err(|err| format!("{}: {:?}", args[0], err))?;
     let count = args[1].parse::<u64>();
     if count.is_err() || count.unwrap() == 0 {
-        return Err(String::from("Expected COUNT to be of type u32"));
+        return Err(String::from("Expected COUNT to be of type u64"));
     }
     Ok(())
 }
@@ -114,21 +104,11 @@ fn grind_validator_starts_and_ends_with(v: String) -> Result<(), String> {
         return Err(String::from("Expected : between PREFIX and SUFFIX and COUNT"));
     }
     let args: Vec<&str> = v.split(':').collect();
-    let p = bs58::decode(&args[0]).into_vec()
-    .map(|_| ())
-    .map_err(|err| format!("{}: {:?}", args[0], err));
-    if p.is_err() {
-        return p;
-    }
-    let s = bs58::decode(&args[1]).into_vec()
-    .map(|_| ())
-    .map_err(|err| format!("{}: {:?}", args[1], err));
-    if s.is_err() {
-        return s;
-    }
+    bs58::decode(&args[0]).into_vec().map_err(|err| format!("{}: {:?}", args[0], err))?;
+    bs58::decode(&args[1]).into_vec().map_err(|err| format!("{}: {:?}", args[1], err))?;
     let count = args[2].parse::<u64>();
     if count.is_err() || count.unwrap() == 0 {
-        return Err(String::from("Expected COUNT to be a u32"));
+        return Err(String::from("Expected COUNT to be a u64"));
     }
     Ok(())
 }