Language/Python/02-Looping.ipynb

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   "source": [
    "# Loop"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### A loop is a programming sructure that repeats a sequence of instructions untill a specific condition is met."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> **Types Of Loops -**\n",
    "There are two types of loop in python.\n",
    "- while loop\n",
    "- for loop"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## while loop"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> **Defination :** while loops repeat as long as a certain boolean condition is met."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Syntax -"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> `while <condition>:\n",
    "    <statement/s>`"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Example -"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "2\n",
      "3\n",
      "4\n",
      "5\n"
     ]
    }
   ],
   "source": [
    "# printing number from 1 to n\n",
    "n = 5\n",
    "count = 1\n",
    "while count <= n:\n",
    "    print(count) #printing number(i.e value of count)\n",
    "    count += 1  #incrementing the value of count by 1"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## for loop"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> **Defination :** for loop iterate over a given sequence."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Syntax -"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> `for <current> in <iterable>:\n",
    "    <statement/s>`"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Example -"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0\n",
      "1\n",
      "2\n",
      "3\n",
      "4\n"
     ]
    }
   ],
   "source": [
    "#printing number from 0 to 4\n",
    "for num in range(5):\n",
    "    print(num)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Note : range() function returns a new list with numbers of that specified range(stating from 0 by default)."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "s\n",
      "t\n",
      "r\n",
      "i\n",
      "n\n",
      "g\n"
     ]
    }
   ],
   "source": [
    "#looping throug a string\n",
    "for char in \"string\":\n",
    "    print(char)"
   ]
  },
  {
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   "metadata": {},
   "source": [
    "## else conditional statement with loops"
   ]
  },
  {
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   "metadata": {},
   "source": [
    "> The else block just after for/while is executed only when the loop is not terminated by a break statement."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Example "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "3\n",
      "5\n",
      "7\n",
      "9\n",
      "No Break!\n"
     ]
    }
   ],
   "source": [
    "#printing odd numbers from 1 to 10\n",
    "for num in range(1,11,2):\n",
    "    print(num)\n",
    "else:\n",
    "    print(\"No Break!\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n",
      "4\n",
      "6\n",
      "8\n",
      "No Break!\n"
     ]
    }
   ],
   "source": [
    "#printing even numbers from 1 to 10\n",
    "num = 2\n",
    "while num < 10:\n",
    "    print(num)\n",
    "    num += 2\n",
    "else:\n",
    "    print(\"No Break!\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Control Statements"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### controls statements are use to control the flow of loops."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    ">control statements are - \n",
    "- break\n",
    "- continue"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## break statement"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    ">break statement is use to exit from the \"while\" or \"for\" loop."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Examples"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "2\n"
     ]
    }
   ],
   "source": [
    "n = 5\n",
    "count = 1\n",
    "while count <= n:\n",
    "    print(count) #printing number(i.e value of count)\n",
    "    count += 1  #incrementing the value of count by 1\n",
    "    if count == 3:\n",
    "        break #it will stop the loop"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0\n",
      "1\n",
      "2\n",
      "3\n"
     ]
    }
   ],
   "source": [
    "for num in range(5):\n",
    "    print(num)\n",
    "    if num == 3:\n",
    "        break"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## continue statement"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> continue is used to skip the current block and return to the for/while statement."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Examples"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "`n = 5\n",
    "count = 1\n",
    "while count <= n:\n",
    "    if count == 3:\n",
    "        continue #it will skip the loop\n",
    "    print(count) #printing number(i.e value of count)\n",
    "    count += 1  #incrementing the value of count by 1\n",
    "'''output\n",
    "1\n",
    "2\n",
    "4'''`"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "`for num in range(5):\n",
    "    if num == 3:\n",
    "        continue\n",
    "    print(num)\n",
    "'''output\n",
    "1\n",
    "2\n",
    "4'''`"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "**This tutorial is intended to be a public resource. As such, if you see any glaring inaccuracies or if a critical topic is missing, please feel free to point it out or (preferably) submit a pull request to improve the tutorial. Also, we are always looking to improve the scope of this article. For anything feel free to mail us @ colearninglounge@gmail.com**"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The author of this article is Surya Prakash Giri.\n",
    "You can follow him on [Github](https://github.com/Akashgiri963), [Linkedin](https://www.linkedin.com/in/surya-prakash-giri-18024a195), [Instagram](https://instagram.com/suryaprakash_giri)."
   ]
  }
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