bug

Author: envyaims

solutions/advanced/ys-PersistentUnionFind.mdx

@@ -38,7 +38,7 @@ struct DSU {
 		if (sz[a] < sz[b]) { swap(a, b); }
 		// add to history
 		past_parent.push_back({b, p[b]});
-		past_size.push_back({a, p[a]});
+		past_size.push_back({a, sz[a]});
 
 		if (a != b) {
 			p[b] = a;