diff --git a/src/logic/board_value.rs b/src/logic/board_value.rs
index 79535c0..c35b676 100644
--- a/src/logic/board_value.rs
+++ b/src/logic/board_value.rs
@@ -6,12 +6,13 @@ impl BoardValueMap {
     pub fn board_value(&self, board: &Board, color: Piece) -> i64 {
         Board::all_positions()
             .filter_map(|(i, j)| board.get(i, j).map(|p| (i, j, p)))
-            .map(|(i, j, pos_p)| {
-                let mut value = *self.0.get(i, j);
+            .map(|(i, j, pos_p)| (*self.0.get(i, j), pos_p))
+            .map(|(value, pos_p)| {
                 if pos_p != color {
                     // enemy has position
-                    value = -value;
+                    return -value;
                 }
+                // target has position
                 value
             })
             .sum()