diff --git a/models/contest.js b/models/contest.js
index 300b00d..ea19bd7 100644
--- a/models/contest.js
+++ b/models/contest.js
@@ -123,9 +123,8 @@ class Contest extends Model {
     let problems = await this.getProblems();
     if (!problems.includes(judge_state.problem_id)) throw new ErrorMessage('当前比赛中无此题目。');
 
-    let player;
-    await syzoj.utils.lock(['Contest::newSubmission', 'create_player', judge_state.user_id], async () => {
-      player = await ContestPlayer.findInContest({
+    await syzoj.utils.lock(['Contest::newSubmission', judge_state.user_id], async () => {
+      let player = await ContestPlayer.findInContest({
         contest_id: this.id,
         user_id: judge_state.user_id
       });
@@ -136,14 +135,14 @@ class Contest extends Model {
           user_id: judge_state.user_id
         });
       }
-    });
 
-    await player.updateScore(judge_state);
-    await player.save();
+      await player.updateScore(judge_state);
+      await player.save();
 
-    await this.loadRelationships();
-    await this.ranklist.updatePlayer(this, player);
-    await this.ranklist.save();
+      await this.loadRelationships();
+      await this.ranklist.updatePlayer(this, player);
+      await this.ranklist.save();
+    });
   }
 
   async isRunning(now) {
diff --git a/models/contest_player.js b/models/contest_player.js
index 044e23b..ac7c402 100644
--- a/models/contest_player.js
+++ b/models/contest_player.js
@@ -69,99 +69,100 @@ class ContestPlayer extends Model {
   }
 
   async updateScore(judge_state) {
-    await syzoj.utils.lock(['ContestPlayer::updateScore', this.id], async () => {
-      await this.loadRelationships();
-      if (this.contest.type === 'ioi') {
-        if (!judge_state.pending) {
-          if (!this.score_details[judge_state.problem_id]) {
-            this.score_details[judge_state.problem_id] = {
-              score: judge_state.score,
-              judge_id: judge_state.id,
-              submissions: {}
-            };
-          }
-
-          this.score_details[judge_state.problem_id].submissions[judge_state.id] = {
-            judge_id: judge_state.id,
+    await this.loadRelationships();
+    if (this.contest.type === 'ioi') {
+      if (!judge_state.pending) {
+        if (!this.score_details[judge_state.problem_id]) {
+          this.score_details[judge_state.problem_id] = {
             score: judge_state.score,
-            time: judge_state.submit_time
+            judge_id: judge_state.id,
+            submissions: {}
           };
+        }
 
-          let arr = Object.values(this.score_details[judge_state.problem_id].submissions);
-          arr.sort((a, b) => a.time - b.time);
-
-          let maxScoreSubmission = null;
-          for (let x of arr) {
-            if (!maxScoreSubmission || x.score >= maxScoreSubmission.score && maxScoreSubmission.score < 100) {
-              maxScoreSubmission = x;
-            }
-          }
+        this.score_details[judge_state.problem_id].submissions[judge_state.id] = {
+          judge_id: judge_state.id,
+          score: judge_state.score,
+          time: judge_state.submit_time
+        };
 
-          this.score_details[judge_state.problem_id].judge_id = maxScoreSubmission.judge_id;
-          this.score_details[judge_state.problem_id].score = maxScoreSubmission.score;
-          this.score_details[judge_state.problem_id].time = maxScoreSubmission.time;
+        let arr = Object.values(this.score_details[judge_state.problem_id].submissions);
+        arr.sort((a, b) => a.time - b.time);
 
-          this.score = 0;
-          for (let x in this.score_details) {
-            this.score += this.score_details[x].score;
+        let maxScoreSubmission = null;
+        for (let x of arr) {
+          if (!maxScoreSubmission || x.score >= maxScoreSubmission.score && maxScoreSubmission.score < 100) {
+            maxScoreSubmission = x;
           }
         }
-      } else if (this.contest.type === 'noi') {
-        this.score_details[judge_state.problem_id] = {
-          score: judge_state.score,
-          judge_id: judge_state.id
-        };
+
+        this.score_details[judge_state.problem_id].judge_id = maxScoreSubmission.judge_id;
+        this.score_details[judge_state.problem_id].score = maxScoreSubmission.score;
+        this.score_details[judge_state.problem_id].time = maxScoreSubmission.time;
+
         this.score = 0;
         for (let x in this.score_details) {
           this.score += this.score_details[x].score;
         }
-      } else if (this.contest.type === 'acm') {
-        if (!judge_state.pending) {
-          if (!this.score_details[judge_state.problem_id]) {
-            this.score_details[judge_state.problem_id] = {
-              accepted: false,
-              unacceptedCount: 0,
-              acceptedTime: 0,
-              judge_id: 0,
-              submissions: {}
-            };
-          }
+      }
+    } else if (this.contest.type === 'noi') {
+      if (this.score_details[judge_state.problem_id] && this.score_details[judge_state.problem_id].judge_id > judge_state.id) return;
 
-          this.score_details[judge_state.problem_id].submissions[judge_state.id] = {
-            judge_id: judge_state.id,
-            accepted: judge_state.status === 'Accepted',
-            compiled: judge_state.status !== 'Compile Error',
-            time: judge_state.submit_time
+      this.score_details[judge_state.problem_id] = {
+        score: judge_state.score,
+        judge_id: judge_state.id
+      };
+
+      this.score = 0;
+      for (let x in this.score_details) {
+        this.score += this.score_details[x].score;
+      }
+    } else if (this.contest.type === 'acm') {
+      if (!judge_state.pending) {
+        if (!this.score_details[judge_state.problem_id]) {
+          this.score_details[judge_state.problem_id] = {
+            accepted: false,
+            unacceptedCount: 0,
+            acceptedTime: 0,
+            judge_id: 0,
+            submissions: {}
           };
+        }
 
-          let arr = Object.values(this.score_details[judge_state.problem_id].submissions);
-          arr.sort((a, b) => a.time - b.time);
-
-          this.score_details[judge_state.problem_id].unacceptedCount = 0;
-          this.score_details[judge_state.problem_id].judge_id = 0;
-          this.score_details[judge_state.problem_id].accepted = 0;
-          for (let x of arr) {
-            if (x.accepted) {
-              this.score_details[judge_state.problem_id].accepted = true;
-              this.score_details[judge_state.problem_id].acceptedTime = x.time;
-              this.score_details[judge_state.problem_id].judge_id = x.judge_id;
-              break;
-            } else if (x.compiled) {
-              this.score_details[judge_state.problem_id].unacceptedCount++;
-            }
-          }
+        this.score_details[judge_state.problem_id].submissions[judge_state.id] = {
+          judge_id: judge_state.id,
+          accepted: judge_state.status === 'Accepted',
+          compiled: judge_state.status !== 'Compile Error',
+          time: judge_state.submit_time
+        };
 
-          if (!this.score_details[judge_state.problem_id].accepted) {
-            this.score_details[judge_state.problem_id].judge_id = arr[arr.length - 1].judge_id;
+        let arr = Object.values(this.score_details[judge_state.problem_id].submissions);
+        arr.sort((a, b) => a.time - b.time);
+
+        this.score_details[judge_state.problem_id].unacceptedCount = 0;
+        this.score_details[judge_state.problem_id].judge_id = 0;
+        this.score_details[judge_state.problem_id].accepted = 0;
+        for (let x of arr) {
+          if (x.accepted) {
+            this.score_details[judge_state.problem_id].accepted = true;
+            this.score_details[judge_state.problem_id].acceptedTime = x.time;
+            this.score_details[judge_state.problem_id].judge_id = x.judge_id;
+            break;
+          } else if (x.compiled) {
+            this.score_details[judge_state.problem_id].unacceptedCount++;
           }
+        }
 
-          this.score = 0;
-          for (let x in this.score_details) {
-            if (this.score_details[x].accepted) this.score++;
-          }
+        if (!this.score_details[judge_state.problem_id].accepted) {
+          this.score_details[judge_state.problem_id].judge_id = arr[arr.length - 1].judge_id;
+        }
+
+        this.score = 0;
+        for (let x in this.score_details) {
+          if (this.score_details[x].accepted) this.score++;
         }
       }
-    });
+    }
   }
 
   getModel() { return model; }