diff --git a/quiz.js b/quiz.js
index abff443..893f413 100644
--- a/quiz.js
+++ b/quiz.js
@@ -133,47 +133,52 @@ function shuffle_cards(section) {
     return a;
 }
 
-function choose_incorrects(idx_vals) {
+function choose_incorrects(elems) {
     let options = {
-        0: [],
+        "-1": [],
     };
-    function find_longest_chain(maxkey) {
-        let longest = null;
-        for (let key in options) {
-            if (
-                (
-                    maxkey == null
-                    || key <= maxkey
-                )
-                && (
-                    longest == null
-                    || options[key].length > options[longest].length
-                    || (
-                        options[key].length == options[longest].length
-                        && Number.parseInt(key) < Number.parseInt(longest)
-                    )
-                )
-            ) {
-                longest = key;
+    function chain_is_better(old_chain, new_chain) {
+        if (old_chain == null) {
+            return true;
+        } else if (new_chain.length > old_chain.length) {
+            return true;
+        } else if (new_chain.length < old_chain.length) {
+            return false;
+        }
+        let old_nums = old_chain.map(elem => elem[1]).sort((a, b) => a - b).reverse();
+        let new_nums = new_chain.map(elem => elem[1]).sort((a, b) => a - b).reverse();
+        for (let i=0; i<old_nums.length; i++) {
+            if (new_nums[i] < old_nums[i]) {
+                return true;
+            } else if (new_nums[i] > old_nums[i]) {
+                return false;
             }
         }
-        return longest;
     }
-    idx_vals.forEach((val) => {
-        let longest = find_longest_chain(val);
-        let mychain = options[longest].slice();
-        mychain.push(val);
-        options[val + 1] = mychain;
-    });
-    let result_chain = find_longest_chain(null);
-    let a = [];
-    for (let i=0; i<cards_content[0].length; i++) {
-        a.push(true);
+    function build_chain(elem) {
+        let best = null;
+        for (let chain_end in options) {
+            let chain = options[chain_end];
+            chain_end = Number.parseInt(chain_end);
+            if (elem == null || chain_end < elem[0]) {
+                let newchain = chain.slice();
+                if (elem != null) {
+                    newchain.push(elem);
+                }
+                if (chain_is_better(best, newchain)) {
+                    best = newchain;
+                }
+            }
+        }
+        return best;
     }
-    options[result_chain].forEach((elem) => {
-        a[elem] = false;
+    elems.forEach(elem => {
+        let chain = build_chain(elem);
+        options[chain[chain.length - 1][0]] = chain;
     });
-    return idx_vals.map(idx => a[idx]);
+    let result_chain = build_chain(null);
+    let corrects = result_chain.map(elem => elem[0]);
+    return elems.map(elem => !corrects.includes(elem[0]));
 }
 
 var app = new Vue({
@@ -185,6 +190,7 @@ var app = new Vue({
             selected: null,
             items: shuffle_cards(0),
         },
+        next_insert_num: null,
         solution: [],
         correction_visible: false,
     },
@@ -274,8 +280,8 @@ var app = new Vue({
                 return this.solution.map(elem => false);
             }
             if (this.store.section == 0) {
-                let idx_vals = this.solution.map(elem => elem.idx[0]);
-                return choose_incorrects(idx_vals);
+                let elems = this.solution.map(elem => [elem.idx[0], elem.insert_num]);
+                return choose_incorrects(elems);
             } else {
                 return this.solution.map((elem, i) => {
                     return elem.idx.length > this.store.section
@@ -316,11 +322,18 @@ var app = new Vue({
         store_card_visible: function(idx) {
             return !this.solution.some(solution => solution.idx[this.store.section] == idx);
         },
+        calculate_insert_num: function() {
+            if (this.next_insert_num == null) {
+                return null;
+            }
+            return this.next_insert_num++;
+        },
         store_select: function(i) {
             if (this.solution.length == 0) {
                 this.solution.push({
                     idx: [i],
                     got_revealed: false,
+                    insert_num: this.calculate_insert_num(),
                 });
             } else if (i == this.store.selected) {
                 this.store.selected = null;
@@ -335,6 +348,7 @@ var app = new Vue({
             this.solution.splice(0, 0, {
                 idx: [this.store.selected],
                 got_revealed: false,
+                insert_num: this.calculate_insert_num(),
             });
             this.store.selected = null;
         },
@@ -349,6 +363,7 @@ var app = new Vue({
             this.solution.splice(this.find_solution(elem)+1, 0, {
                 idx: [this.store.selected],
                 got_revealed: false,
+                insert_num: this.calculate_insert_num(),
             });
             this.store.selected = null;
         },
@@ -360,6 +375,12 @@ var app = new Vue({
             }
         },
         show_correction: function() {
+            if (this.store.section == 0) {
+                this.solution.forEach((elem, i) => {
+                    elem.insert_num = -i;
+                });
+                this.next_insert_num = 1;
+            }
             this.correction_visible = true;
         },
         open_next_column: function() {