core: fix problem count for search

packages/hydrooj/src/handler/problem.ts

@@ -193,6 +193,8 @@ export class ProblemMainHandler extends Handler {
                 pcount = pcount - count + pdocs.length;
             }
         }
+        // some problems are hidden and cannot be viewed by current user
+        if (pcount > pdocs.length) pcount = pdocs.length;
         if (this.user.hasPriv(PRIV.PRIV_USER_PROFILE)) {
             const domainIds = Array.from(new Set(pdocs.map((i) => i.domainId)));
             await Promise.all(