almost done

Author: jmportilla

Mock Interviews/Social Network Company/Social Network Company - Interview Questions - SOLUTIONS/.ipynb_checkpoints/On-Site Question 2 - SOLUTION-checkpoint.ipynb

@@ -15,14 +15,51 @@
     "** Do not use built-in Python functions or methods **"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Solution\n",
+    "\n",
+    "This should feel very familiar to one of the problems we did in the array section of the course! We can use an [XOR](https://en.wikipedia.org/wiki/Exclusive_or) operation. The **exclusive or** operations will take two sets of bits and for each pair it will return a 1 value if **one but not both** of the bits is 1.\n",
+    "\n",
+    "In Python we can use the ^ symbol to perform an XOR.\n",
+    "\n",
+    "Now for our solution we can simply XOR all the integers in the list. We start with a unique id set to 0, then every time we XOR a new id from the list, it will change the bits. When we XOR with the same ID again, it will cancel out the earlier change.\n",
+    "\n",
+    "By the end, we wil be left with the ID that was unique and only appeared once!"
+   ]
+  },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 2,
    "metadata": {
     "collapsed": true
    },
    "outputs": [],
-   "source": []
+   "source": [
+    "def solution(id_list):\n",
+    "    \n",
+    "    # Initiate unique Id\n",
+    "    unique_id = 0\n",
+    "    \n",
+    "    # XOR fo revery id in id list\n",
+    "    for i in id_list:\n",
+    "        \n",
+    "        # XOR operation\n",
+    "        unique_id ^= i\n",
+    "    \n",
+    "    return unique_id"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Good Job!"
+   ]
   }
  ],
  "metadata": {

Mock Interviews/Social Network Company/Social Network Company - Interview Questions - SOLUTIONS/On-Site Question 2 - SOLUTION.ipynb

@@ -15,14 +15,51 @@
     "** Do not use built-in Python functions or methods **"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "collapsed": true
+   },
+   "source": [
+    "## Solution\n",
+    "\n",
+    "This should feel very familiar to one of the problems we did in the array section of the course! We can use an [XOR](https://en.wikipedia.org/wiki/Exclusive_or) operation. The **exclusive or** operations will take two sets of bits and for each pair it will return a 1 value if **one but not both** of the bits is 1.\n",
+    "\n",
+    "In Python we can use the ^ symbol to perform an XOR.\n",
+    "\n",
+    "Now for our solution we can simply XOR all the integers in the list. We start with a unique id set to 0, then every time we XOR a new id from the list, it will change the bits. When we XOR with the same ID again, it will cancel out the earlier change.\n",
+    "\n",
+    "By the end, we wil be left with the ID that was unique and only appeared once!"
+   ]
+  },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 2,
    "metadata": {
     "collapsed": true
    },
    "outputs": [],
-   "source": []
+   "source": [
+    "def solution(id_list):\n",
+    "    \n",
+    "    # Initiate unique Id\n",
+    "    unique_id = 0\n",
+    "    \n",
+    "    # XOR fo revery id in id list\n",
+    "    for i in id_list:\n",
+    "        \n",
+    "        # XOR operation\n",
+    "        unique_id ^= i\n",
+    "    \n",
+    "    return unique_id"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Good Job!"
+   ]
   }
  ],
  "metadata": {