add check for 0 queries in get_mean_price

src/bin/means_to_an_end.rs

@@ -58,8 +58,9 @@ fn get_mean_price(insertions: &Vec<InsertData>, query: &QueryData) -> i32 {
         .map(|i| i.price)
         .collect();
 
+
     // safe?
-    prices.iter().sum::<i32>() / prices.len() as i32
+    if prices.len() > 0 { prices.iter().sum::<i32>() / prices.len() as i32 } else { 0 }
 }
 
 const PORT: usize = 10001;