diff --git a/analysis-master/analysis-amd64/analysis/equation.ipynb b/analysis-master/analysis-amd64/analysis/equation.ipynb
index b8c86e18..58b5c57f 100644
--- a/analysis-master/analysis-amd64/analysis/equation.ipynb
+++ b/analysis-master/analysis-amd64/analysis/equation.ipynb
@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "code",
-   "execution_count": 61,
+   "execution_count": 28,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -13,7 +13,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 62,
+   "execution_count": 29,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -25,11 +25,31 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 63,
+   "execution_count": 30,
    "metadata": {},
    "outputs": [],
    "source": [
-    "def multiply(string):\n",
+    "def sub(string):\n",
+    "    while(len(re.findall(\"\\d+[.]?\\d*[-]{1,2}\\d+[.]?\\d*\", string)) != 0):\n",
+    "        g = re.search(\"\\d+[.]?\\d*[-]{1,2}\\d+[.]?\\d*\", string).group()\n",
+    "        if(re.search(\"[-]{1,2}\", g).group() == \"-\"):\n",
+    "            r = re.sub(\"[-]{1}\", \"+-\", g, 1)\n",
+    "            string = re.sub(g, r, string, 1)\n",
+    "        elif(re.search(\"[-]{1,2}\", g).group() == \"--\"):\n",
+    "            r = re.sub(\"[-]{2}\", \"+\", g, 1)\n",
+    "            string = re.sub(g, r, string, 1)\n",
+    "        else:\n",
+    "            pass\n",
+    "    return string"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 31,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def mul(string):\n",
     "    while(len(re.findall(\"[*]{1}[-]?\", string)) != 0):\n",
     "        string = re.sub(\"[-]?\\d+[.]?\\d*[*]{1}[-]?\\d+[.]?\\d*\", str(reduce((lambda x, y: x * y), [Decimal(i) for i in re.split(\"[*]{1}\", re.search(\"[-]?\\d+[.]?\\d*[*]{1}[-]?\\d+[.]?\\d*\", string).group())])), string, 1)\n",
     "    return string"
@@ -37,21 +57,48 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 69,
+   "execution_count": 32,
    "metadata": {},
    "outputs": [
     {
      "output_type": "stream",
      "name": "stdout",
-     "text": "-29\n"
+     "text": "-30\n"
     }
    ],
    "source": [
-    "string = \"-3+4+-5*6\"\n",
-    "string = multiply(string)\n",
-    "string = add(string)\n",
-    "print(string)"
+    "def eval(string):\n",
+    "    string = mul(string)\n",
+    "    string = sub(string)\n",
+    "    string = add(string)\n",
+    "    return string"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 34,
+   "metadata": {},
+   "outputs": [
+    {
+     "output_type": "execute_result",
+     "data": {
+      "text/plain": "-22"
+     },
+     "metadata": {},
+     "execution_count": 34
+    }
+   ],
+   "source": [
+    "string = \"2--3+4-5*6-1\"\n",
+    "eval(string)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {