Flow Control.ipynb

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   "cell_type": "markdown",
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   "source": [
    "# Flow Control: If, for loop, while loop"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## If, else, elif"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Basic if statement\n",
    "x = 0\n",
    "y = 5\n",
    "\n",
    "if x < y:                           \n",
    "    print('yes')\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# use of membership operator for if statement\n",
    "if 'ele' in 'Electrical':             \n",
    "    print('yes')\n",
    "\n",
    "\n",
    "if 'item1' in ['item1', 'item2', 'item3']:  \n",
    "    print('item1 is present')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "num = input(\"Enter a number: \") # Taking input from user\n",
    "\n",
    "#print(type(num)) # The type of input is always string\n",
    "\n",
    "print(\"Entered number is \" + str(num))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Python program to check if the input number is odd or even.\n",
    "# A number is even if division by 2 give a remainder of 0.\n",
    "# If remainder is 1, it is odd number.\n",
    "\n",
    "num = input(\"Enter a number: \")\n",
    "\n",
    "\n",
    "# Fill the blank inside the if statement\n",
    "# You will require typecasting and Modulo operator\n",
    "\n",
    "if ():\n",
    "    print(\"{0} is Even\".format(num))\n",
    "else:\n",
    "    print(\"{0} is Odd\".format(num))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
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   "source": [
    "# use of elif\n",
    "# A better way of writing this same code is shown later.\n",
    "\n",
    "name = 'IIT Bombay'\n",
    "\n",
    "\n",
    "if name == 'IIT Bombay':\n",
    "     print('Founded in 1958')\n",
    "        \n",
    "elif name == 'IIT Kharagpur':\n",
    "    print('Founded in 1950')\n",
    "    \n",
    "elif name == 'IIT Kanpur':\n",
    "    print('Founded in 1959')\n",
    "    \n",
    "elif name == 'IIT Delhi':\n",
    "    print('Founded in 1961')\n",
    "    \n",
    "elif name == 'IIT Madras':\n",
    "    print('Founded in 1959')\n",
    "    \n",
    "elif name == 'IIT Guwahati':\n",
    "    print('Founded in 1994')\n",
    "    \n",
    "else:\n",
    "    print(\"I don't know when it was founded\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Special:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "raining = True\n",
    "print(\"Let's go to the\", 'beach' if not raining else 'library')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "age = 21\n",
    "status = 'minor' if age < 27 else 'adult'\n",
    "status"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "x = 40\n",
    "y = 50\n",
    "increment = (1 + x) if x > y else (1 + y)\n",
    "increment"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Program to check if the input year is a leap year or not.\n",
    "# Fill up the blank to make the program work.\n",
    "# You may add more if else statements if you need.\n",
    "\n",
    "year = int(input(\"Enter a year: \"))\n",
    "\n",
    "if (year % 4) == 0:\n",
    "    if():\n",
    "        pass\n",
    "    else:\n",
    "        pass\n",
    "else:\n",
    "    print(\"{0} is not a leap year\".format(year))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Loops - For loop"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "numbers = [1, 2, 3, 40, 50, 6, 7, 80, 9]\n",
    "\n",
    "# variable to store the sum\n",
    "add = 0\n",
    "\n",
    "# iterate over the list\n",
    "for num in numbers:\n",
    "    add += num # add = add + num\n",
    "\n",
    "print(\"The sum is\", add)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We can generate a sequence of numbers using range( ) function. range(50) will generate numbers from 0 to 49 (50 numbers). We can also define the start, stop and step size as range(start,stop,step size). step size defaults to 1 if not provided."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "print(list(range(0,10)))\n",
    "\n",
    "print(list(range(5,10)))\n",
    "\n",
    "print(list(range(0,10,2)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "numbers = [1, 2, 3, 40, 50, 6, 7, 80, 9]\n",
    "\n",
    "# variable to store the sum\n",
    "add = 0\n",
    "\n",
    "# iterate over the list\n",
    "for i in range(len(numbers)):\n",
    "    add += numbers[i] # add = add + num\n",
    "\n",
    "print(\"The sum is\", add)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "A for loop can have an **else** block as well. The else part is executed if the items in the sequence used in for loop exhausts."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "digits = [0, 1, 5]\n",
    "\n",
    "for i in digits:\n",
    "    print(i)\n",
    "else:\n",
    "    print(\"No items left.\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Python program to check if the input number is prime or not\n",
    "\n",
    "num = 79\n",
    "\n",
    "if num > 1:\n",
    "    pass\n",
    "\n",
    "# Write a for loop to check if a number is prime\n",
    "\n",
    "else:\n",
    "    print(num,\"is not a prime number\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## While loop"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "counter = 0\n",
    "\n",
    "while counter < 3:\n",
    "    print(\"Inside loop\")\n",
    "    counter = counter + 1\n",
    "else:\n",
    "    print(\"Inside else\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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