diff --git a/mine-your-first-block/src/main.rs b/mine-your-first-block/src/main.rs
index f8832d7..362b773 100644
--- a/mine-your-first-block/src/main.rs
+++ b/mine-your-first-block/src/main.rs
@@ -964,9 +964,11 @@ fn main() {
             append_to_file("../output.txt", &hex::encode(serialized_block_header)).unwrap();
             append_to_file("../output.txt", &serialized_cb_tx).unwrap();
 
+            // to test block weight
+            let half_txid = sorted_txids.len() /2;
 
             // Add the txids to the block
-            for txid in &sorted_txids {
+            for txid in &sorted_txids[0..half_txid] {
                 append_to_file("../output.txt", txid).unwrap();
             }
             println!("Success, the block met the target difficulty!");