diff --git a/src/coin_grinder.rs b/src/coin_grinder.rs
index a6af78e..39d68d0 100644
--- a/src/coin_grinder.rs
+++ b/src/coin_grinder.rs
@@ -454,4 +454,36 @@ mod tests {
 
         assert_coin_select_params(&params, Some(&["1 BTC", "1 BTC"]));
     }
+
+    #[test]
+    fn tmp() {
+        let mut coins = Vec::new();
+
+        for i in 0..5 {
+            // Heavy: 3, 6, 9, 12, 15,
+            let heavy = 3 + 3 * i;
+            coins.push(heavy);
+
+            // Medium: 2, 5, 8, 11, 14
+            let medium = 2 + 3 * i;
+            coins.push(medium);
+
+            // Light: 1, 4, 7, 10, 13
+            let light = 1 + 3 * i;
+            coins.push(light);
+        }
+
+        let c: Vec<String> = coins.iter().map(|a| format!("{} BTC", a)).collect();
+        let v4: Vec<&str> = c.iter().map(|s| s as &str).collect();
+
+        let params = ParamsStr {
+            target: "30 BTC",
+            change_target: "1000000 sats",
+            max_weight: "400000",
+            fee_rate: "5",
+            weighted_utxos: v4 
+        };
+
+        assert_coin_select_params(&params, Some(&["14 BTC", "13 BTC", "4 BTC"]));
+    }
 }