{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Problem Set 1 (PS 1)\n",
"\n",
"Complete the 4 functions as directed to:\n",
"\n",
"- validate the format of a string, without regular expressions\n",
"- compute probabilities and store them in a lookup table\n",
"- generate a string deterministically based on a given string\n",
"\n",
"Each function is worth 1 to 4 points, for a total of 10 points. Other assignments will be more complicated, and worth more points, for this I just want to make sure you are in the correct course. I care mainly about correctness of the implementation, but reserve the right to deduct points for code that is difficult to read.\n",
"\n",
"This assignment will test your skills at implementing algorithms in Python from scratch. If this is your first experience with traditional programming structures, then it may take some time to figure everything out. Please schedule time to meet with meet with me if you need help. I recommend you start early. For others, it will not take long.\n",
"\n",
"## Submission Instructions\n",
"\n",
"After completing the exercises below, generate a pdf of the code **with** outputs. After that create a zip file containing both the completed exercise and the generated PDF/HTML. You are **required** to check the PDF/HTML to make sure all the code **and** outputs are clearly visible and easy to read. If your code goes off the page, you should reduce the line size. I generally recommend not going over 80 characters.\n",
"\n",
"Finally, name the zip file using a combination of your the assigment and your name, e.g., ps1_rios.zip\n"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Exercise 1 (4 points)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"Checks whether the string is a valid employee ID using a single regular expression. An employee ID is valid if and only if it consists only of 6-10 alphabetic characters (letters), followed by 2 numeric digits. Implement the validation **without **using a regex or any libraries. You may use the .isalpha() and .isdigit() methods, variables, standard data structures such as lists, if statements, loops, etc."
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [],
"source": [
"def validate(s):\n",
" if (len(s)<2 or not s[-2:].isdigit()):\n",
" return False\n",
" \n",
" s1 = s[:-2]\n",
" if ((len(s1)<6) or (len(s1)>10) or not s1.isalpha()):\n",
" return

5 (30 marks) User defined data structures The code for this ques...