diff --git a/src/cap.js b/src/cap.js
index 2014f58..2bc6c97 100644
--- a/src/cap.js
+++ b/src/cap.js
@@ -32,7 +32,6 @@ $("*").click(function() {
 function cal_cap() {
 
     let mods_taken_raw = JSON.parse(localStorage.getItem('persist:planner'));
-    let all_mods_info_raw = JSON.parse(localStorage.getItem('persist:moduleBank'));
     let modcodes_array = get_modcodes_array(mods_taken_raw);
     // console.log(modcodes_array);
 
@@ -47,10 +46,10 @@ function cal_cap() {
 
     try {
         let mods_taken_grade = JSON.parse(localStorage.getItem('YSL:data'));
+        let all_mods_info_raw = JSON.parse(localStorage.getItem('persist:moduleBank'));
         let mods_taken_info_cap = get_mods_taken_info(modcodes_array, all_mods_info_raw, mods_taken_grade);
 
         // console.log(mods_taken_info_cap);
-
         let cap = calculate_cap(mods_taken_info_cap);
         return cap;
     } catch(err) {
@@ -93,10 +92,32 @@ function update_YSL_data(modcodes_array) {
         console.log("Error in updating YSL data! have modules:" + modcodes_array + "but data not present in YSL data");
     } else {
         localStorage.setItem('YSL:data', JSON.stringify(new_mods_taken_grade));
+        SULeft();
     }
 }
 
-
+// same function as the one in grade.js
+function SULeft() {
+    const ysl_data = JSON.parse(localStorage.getItem('YSL:data'));
+    if (!ysl_data) {
+      localStorage.setItem('YSL:SUleft', total_SU);
+      return total_SU;
+    }
+    const modules = JSON.parse(JSON.parse(localStorage.getItem('persist:moduleBank'))['modules']);
+    // console.log("su_left: "+count);
+    // console.log(ysl_data);
+    // const su_left = total_SU - Object.keys(ysl_data).reduce((acc, cur) => acc + ysl_data[cur]['su'] ? modules[cur]['moduleCredit'] : 0, 0);
+    let su_left = total_SU;
+    for(let mod_code in ysl_data) {
+      if (ysl_data[mod_code]['su']) {
+         su_left -= modules[mod_code]['moduleCredit'];
+      }
+    }
+    localStorage.setItem('YSL:SUleft', su_left);
+    // console.log('......' + su_left);
+    // count++;
+    return su_left;
+  }
 
 function get_modcodes_array(mods_taken_raw) {
     let res = [];
@@ -117,12 +138,19 @@ function get_mods_taken_info(modcodes_array, all_mods_info_raw, mods_taken_grade
     for (let i = 0; i < modcodes_array.length; i++) {
         let mod_code = modcodes_array[i];
         let mc, grade, su;
-        if (all_mods_info.hasOwnProperty(mod_code)) {
+        // if (all_mods_info.hasOwnProperty(mod_code)) {
+        //     mc = parseInt(all_mods_info[mod_code]['moduleCredit']);
+        // } else {
+        //     console.log('Error: CAP calculator, no MC info for' + mod_code);
+        //     mc = 0;
+        // }
+        if (all_mods_info[mod_code]) {
             mc = parseInt(all_mods_info[mod_code]['moduleCredit']);
         } else {
             console.log('Error: CAP calculator, no MC info for' + mod_code);
             mc = 0;
         }
+
         if (mods_taken_grade.hasOwnProperty(mod_code)) {
             grade = mods_taken_grade[mod_code]['grade'];
             if (grade === "") {
@@ -217,9 +245,9 @@ function calculate_cap(courses) {
 
 // the followings functions involve the SUs
 function get_su(){
-    if (localStorage.getItem('YSL:SUleft') === null) {
+    if (localStorage.getItem('YSL:SUleft') === null ) {
         return "32";
-    }
+    } 
     return ""+localStorage.getItem('YSL:SUleft');
 }
 
diff --git a/src/grade.js b/src/grade.js
index 5726d8e..f64198e 100644
--- a/src/grade.js
+++ b/src/grade.js
@@ -1,7 +1,10 @@
 $(document).ready(function () {
   add_editModules_listener();
   add_ModuleCards_listener();
+  // add_Remove_listener();
+
   add_Click_listener();
+
 });
 
 function add_editModules_listener() {
@@ -39,6 +42,19 @@ function add_Click_listener() {
   });
 }
 
+function add_Remove_listener() {
+  $("body").click(function () {
+    $("button:contains('Remove')").click(
+      checkSU_when_remove
+    );
+    // console.log("removed one mod, su rebalanced");
+  });
+}
+function checkSU_when_remove() {
+  setTimeout(function() {
+    SULeft();
+  }, 50);
+}
 function toggleSU() {
   console.log($(this).find("strong").text());
   const mod_code = $(this).find("strong").text();
@@ -196,6 +212,7 @@ function updateEditModal() {
 
 var total_SU = 32;
 
+// var count = 0;
 function SULeft() {
   const ysl_data = JSON.parse(localStorage.getItem('YSL:data'));
   if (!ysl_data) {
@@ -203,7 +220,15 @@ function SULeft() {
     return total_SU;
   }
   const modules = JSON.parse(JSON.parse(localStorage.getItem('persist:moduleBank'))['modules']);
-  const su_left = total_SU - Object.keys(ysl_data).reduce((acc, cur) => acc + ysl_data[cur]['su'] ? modules[cur]['moduleCredit'] : 0, 0);
+  // console.log("su_left: "+count);
+  // console.log(ysl_data);
+  // const su_left = total_SU - Object.keys(ysl_data).reduce((acc, cur) => acc + ysl_data[cur]['su'] ? modules[cur]['moduleCredit'] : 0, 0);
+  let su_left = total_SU;
+  for(let mod_code in ysl_data) {
+    if (ysl_data[mod_code]['su']) {
+       su_left -= modules[mod_code]['moduleCredit'];
+    }
+  }
   localStorage.setItem('YSL:SUleft', su_left);
   return su_left;
 }
@@ -241,7 +266,12 @@ function addSUSelector(mod, grade) {
 }
 
 function showDropdownList() {
+  // setTimeout(function () {
+  //   // console.log('new modal!!!');
+  //   updateEditModal();
+  // }, 0);
   setTimeout(function () {
     updateEditModal();
   }, 0);
+  
 }