diff --git a/lib/prim.c b/lib/prim.c
index e231728..ff3f58c 100644
--- a/lib/prim.c
+++ b/lib/prim.c
@@ -39,7 +39,7 @@ void prim(mazegrid_t const* g, mazegrid_t* result) {
         }
         if ((e.x < g->width - 1) && !node_set_contains(s, e.x + 1, e.y)) {
             _point_t pt = { e.x + 1, e.y, EDGE_LEFT };
-            PUSH_PQ(q, PointPQ, pt, mazegrid_get_edge(g, e.x, e.y, EDGE_LEFT));
+            PUSH_PQ(q, PointPQ, pt, mazegrid_get_edge(g, e.x, e.y, EDGE_RIGHT));
         }
         if ((e.y > 0) && !node_set_contains(s, e.x, e.y - 1)) {
             _point_t pt = { e.x, e.y - 1, EDGE_UP };