Control Statements.ipynb

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    "### Control Statements\n",
    "\n",
    "Control Statements are mostly common in all the programming languages to decide what to do, how to do and number of times should do\n",
    "\n",
    "#### IF Statement\n",
    "```\n",
    "    if <expression>:\n",
    "        <statements>\n",
    "    elif <expression>:\n",
    "        <statements>\n",
    "    else:\n",
    "        <statements>\n",
    "```\n",
    "\n",
    "You can add **multiple elif** (else if) in a nested way or just go with **simple if** (only if, without elif and else) or **can use if along with else** (without elif)\n",
    "\n",
    "<hr>\n",
    "\n",
    "#### FOR Statement\n",
    "```\n",
    "    for <user_defined_variable> in <lists or range>:\n",
    "        <statements>\n",
    "```\n",
    "\n",
    "### WHILE Statement\n",
    "```\n",
    "    while <expression>:\n",
    "        <statements>\n",
    "```\n",
    "\n",
    "**range()** function is a function which creates a list in a sequence manner\n",
    "```\n",
    "        range(1,4)  # 1,2,3\n",
    "        range(4)    # 0,1,2,3\n",
    "        range(1,10,2) # 1,3,5,7,9\n",
    "```"
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    "#### Example\n",
    "\n",
    "1. ```\n",
    "    a = 10\n",
    "    if a > 5:\n",
    "        print('Greater than five')\n",
    "    elif a < 5:\n",
    "        print('Lesser than five')\n",
    "    else:\n",
    "        print('Equals to five')\n",
    "  ```\n",
    "\n",
    "<hr>\n",
    "\n",
    "2. ```\n",
    "    for i in range(10):\n",
    "        print(i)\n",
    "   ```"
   ]
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    "#### Break\n",
    "\n",
    "**break** statement in a python can be used to terminate a **loop** without executing all the iterations when satisfying certain condition(s)\n",
    "\n",
    "```\n",
    "    for i in range(1, 5):\n",
    "        if i % 2 == 0:\n",
    "            break;\n",
    "        print(i)\n",
    "```\n",
    "\n",
    "#### Continue\n",
    "**continue** statement in a python can be used to go to next iteration in a **loop** when certain condition(s) satisfied without executing a further statements after the **continue** statement\n",
    "\n",
    "```\n",
    "    for i in range(1, 5):\n",
    "        if i % 2 == 0:\n",
    "            continue;\n",
    "        print(i)\n",
    "```\n",
    "\n",
    "#### Pass\n",
    "**pass** statement in a python used to when a statement is required syntactically, but the no action required by the program\n",
    "```\n",
    "    for i in range(0,5):\n",
    "        pass\n",
    "```\n",
    "\n",
    "When you observed carefully the above snippet of **pass** statement, I want to execute a **for loop** five times but I don't know what to execute inside the **for loop**. Portion of statements may be added in future"
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    "### Function\n",
    "\n",
    "Functions are the primary component in all the programming languages which is mainly used to divide the lenthier code into a small portions\n",
    "\n",
    "```\n",
    "   def <function_name>(parameter_1, parameter_2, [...]):\n",
    "       <statements>\n",
    "       [return]\n",
    "```\n",
    "\n",
    "In Python, no need to define any return type of the function and even **return** statement also an optional\n",
    "\n",
    "```\n",
    "    def list_numbers(n):\n",
    "        a = []\n",
    "        for i in range(n):\n",
    "            a.append(i)\n",
    "        print(a)\n",
    "        return a\n",
    "        \n",
    "    list_numbers(6)                 # Comment the return statement in list_numbers()\n",
    "    print(list_numbers(6))          # Comment the print statement in list_numbers()\n",
    "```\n",
    "\n",
    "**Note:** - To know more about defining functions especially Positional/Keyword Parameters, [Click here](https://docs.python.org/3.8//tutorial/controlflow.html)\n",
    "\n",
    "#### lambda function\n",
    "\n",
    "**lambda function** is an anonymous function which can expressed in a single line of statements\n",
    "\n",
    "```\n",
    "a = lambda x: x + 2\n",
    "print(a(2))\n",
    "print([a(i) for i in range(5)])\n",
    "```"
   ]
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