Fix default language in problem submit

views/problem.ejs

@@ -310,7 +310,7 @@ div[class*=ace_br] {
                 <div class="four wide column" style="margin-right: -25px; ">
                   <div class="ui attached vertical fluid pointing menu" id="languages-menu" style="height: 370px; overflow-y: scroll; overflow-x: hidden; ">
                     <%
-                    let language = syzoj.config.enabled_languages;
+                    let language = syzoj.config.enabled_languages[0];
                     if (state) {
                       language = state.language;
                     } else if (lastLanguage) language = lastLanguage;