docstring added to cryptography

Author: BBEK-Anand

cryptography/des_key_generation.ipynb

@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "code",
-   "execution_count": 1,
+   "execution_count": 8,
    "id": "8561e0a7",
    "metadata": {},
    "outputs": [
@@ -26,7 +26,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 2,
+   "execution_count": 7,
    "id": "12f36b2f",
    "metadata": {},
    "outputs": [
@@ -36,27 +36,38 @@
        "21"
       ]
      },
-     "execution_count": 2,
+     "execution_count": 7,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "def eucld_gcd(a,b):\n",
-    "    if(a < b):\n",
-    "        a , b = b , a\n",
-    "    if(b==0):\n",
+    "def eucld_gcd(a, b):\n",
+    "    \"\"\"\n",
+    "    Computes the greatest common divisor (GCD) of two integers using the Euclidean algorithm.\n",
+    "\n",
+    "    Parameters:\n",
+    "    a (int): The first integer.\n",
+    "    b (int): The second integer.\n",
+    "\n",
+    "    Returns:\n",
+    "    int: The greatest common divisor of a and b.\n",
+    "    \"\"\"\n",
+    "    if a < b:\n",
+    "        a, b = b, a\n",
+    "    if b == 0:\n",
     "        return a\n",
-    "    r = a%b\n",
-    "    if(r==0):\n",
+    "    r = a % b\n",
+    "    if r == 0:\n",
     "        return b\n",
-    "    return eucld_gcd(b,r)\n",
+    "    return eucld_gcd(b, r)\n",
+    "\n",
     "eucld_gcd(252,105)"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": 9,
    "id": "c060ee17",
    "metadata": {},
    "outputs": [
@@ -66,45 +77,65 @@
        "[1, -48]"
       ]
      },
-     "execution_count": 3,
+     "execution_count": 9,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
     "import numpy as np\n",
-    "def ext_eucld(a,b):\n",
+    "\n",
+    "def ext_eucld(a, b):\n",
+    "    \"\"\"\n",
+    "    Computes the extended Euclidean algorithm to find the greatest common divisor (GCD)\n",
+    "    of two integers, and also the coefficients (x, y) of the equation:\n",
+    "    a*x + b*y = GCD(a, b)\n",
+    "\n",
+    "    This method returns the coefficients (x, y) such that a*x + b*y = GCD(a, b).\n",
+    "\n",
+    "    Parameters:\n",
+    "    a (int): The first integer.\n",
+    "    b (int): The second integer.\n",
+    "\n",
+    "    Returns:\n",
+    "    list: A list of two integers [x, y] where x and y are the coefficients for the linear\n",
+    "          combination of a and b that equals their GCD.\n",
+    "    \"\"\"\n",
     "    swap = False\n",
-    "    if(a < b):\n",
-    "            a , b = b , a\n",
-    "            swap = True\n",
-    "    def eucld(a,b):\n",
-    "        if(b==0 or b==1):\n",
+    "    if a < b:\n",
+    "        a, b = b, a\n",
+    "        swap = True\n",
+    "\n",
+    "    def eucld(a, b):\n",
+    "        if b == 0 or b == 1:\n",
     "            return []\n",
     "        ls = []\n",
-    "        while b!=1:\n",
-    "            r = a%b\n",
-    "            if(r==0):\n",
+    "        while b != 1:\n",
+    "            r = a % b\n",
+    "            if r == 0:\n",
     "                return ls\n",
-    "            idx = (a-r)//b\n",
+    "            idx = (a - r) // b\n",
     "            ls.append(idx)\n",
     "            a = b\n",
     "            b = r\n",
     "        return ls\n",
-    "    \n",
-    "    row = np.array([[1,0],[0,1]])\n",
-    "    ls = eucld(a,b)\n",
+    "\n",
+    "    row = np.array([[1, 0], [0, 1]])\n",
+    "    ls = eucld(a, b)\n",
     "    for i in ls:\n",
-    "        row = np.append(row, [row[-2] - i*row[-1]] ,axis=0)\n",
-    "    if(swap):\n",
+    "        row = np.append(row, [row[-2] - i * row[-1]], axis=0)\n",
+    "    \n",
+    "    if swap:\n",
     "        return list(row[-1])[::-1]\n",
+    "    \n",
     "    return list(row[-1])\n",
-    "ext_eucld(97,2)"
+    "\n",
+    "ext_eucld(97, 2)\n"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": 10,
    "id": "d3edd1f6",
    "metadata": {},
    "outputs": [