core: fix contest.isOngoing

packages/hydrooj/package.json

@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "2.14.2",
+    "version": "2.14.3",
     "bin": "bin/hydrooj.js",
     "main": "dist/loader.js",
     "typings": "dist/loader.d.ts",

packages/hydrooj/src/handler/contest.ts

@@ -272,7 +272,7 @@ class ContestProblemSubmitHandler extends ContestProblemHandler {
     @param('tid', Types.ObjectID)
     @param('pid', Types.UnsignedInt)
     async prepare(domainId: string, tid: ObjectID, pid: number) {
-        if (contest.isOngoing(this.tdoc)) throw new ContestNotLiveError(this.tdoc.docId);
+        if (!contest.isOngoing(this.tdoc)) throw new ContestNotLiveError(this.tdoc.docId);
         let rdocs = [];
         if (this.canShowRecord(this.tdoc)) {
             rdocs = await record.getUserInProblemMulti(