From f51d94edcaf89939f55550add918aeb1fbaa0554 Mon Sep 17 00:00:00 2001
From: undefined <i@undefined.moe>
Date: Wed, 29 Jun 2022 12:24:17 +0800
Subject: [PATCH] judge: objective: allow empty answers

---
 packages/hydrojudge/package.json           | 2 +-
 packages/hydrojudge/src/judge/objective.ts | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/hydrojudge/package.json b/packages/hydrojudge/package.json
index d9bf6181..9dda2098 100644
--- a/packages/hydrojudge/package.json
+++ b/packages/hydrojudge/package.json
@@ -1,7 +1,7 @@
 {
     "name": "@hydrooj/hydrojudge",
     "bin": "bin/hydrojudge.js",
-    "version": "2.21.0",
+    "version": "2.21.1",
     "main": "package.json",
     "author": "undefined <i@undefined.moe>",
     "repository": "https://github.com/hydro-dev/Hydro.git",
diff --git a/packages/hydrojudge/src/judge/objective.ts b/packages/hydrojudge/src/judge/objective.ts
index 0ac58849..729fb4ea 100644
--- a/packages/hydrojudge/src/judge/objective.ts
+++ b/packages/hydrojudge/src/judge/objective.ts
@@ -39,7 +39,7 @@ export async function judge({
             memory: 0,
         };
         if (typeof ansInfo[0] === 'string') {
-            if (ansInfo[0].trim() === (answers[key] as any).trim()) {
+            if (ansInfo[0]?.trim() === (answers[key] as any)?.trim()) {
                 totalScore += score;
                 totalStatus = Math.max(totalStatus, STATUS.STATUS_ACCEPTED);
                 next({
@@ -64,8 +64,8 @@ export async function judge({
                 }, +caseId);
             }
         } else {
-            const stdAns = new Set(ansInfo[0]);
-            const ans = new Set(answers[key]);
+            const stdAns = new Set(ansInfo[0] || []);
+            const ans = new Set(answers[key] || []);
             const correct = stdAns.size === ans.size && [...stdAns].every((x) => ans.has(x));
             const partialCorrect = [...stdAns].some((x) => ans.has(x)) && [...ans].every((x) => stdAns.has(x));
             if (correct) {