intro to for loops.ipynb

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     "text": [
      "3\n",
      "10\n",
      "-1\n"
     ]
    }
   ],
   "source": [
    "#to print all elements of list: naive approach\n",
    "\n",
    "a=[3,10,-1]\n",
    "print(a[0])\n",
    "print(a[1])\n",
    "print(a[2])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "3\n",
      "10\n",
      "-1\n"
     ]
    }
   ],
   "source": [
    "#if the list had 100 or 1000 elements, it would be tiresome to write that many print statments\n",
    "\n",
    "#so we use fo loops\n",
    "\n",
    "for element in a:\n",
    "    print(element)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "banana\n",
      "apple\n",
      "microsoft\n"
     ]
    }
   ],
   "source": [
    "b=[\"banana\",\"apple\",\"microsoft\"]\n",
    "\n",
    "for e in b:\n",
    "    print(e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "12\n"
     ]
    }
   ],
   "source": [
    "#to find sum of elements in a list\n",
    "sum=0\n",
    "for e in a:\n",
    "    sum=sum+e\n",
    "print(sum)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "#lists of numbers from 1 to 10 can be created in a shortcut way rather than mentioning all the elements:1,2,3....\n",
    "# we use range function to define a range of numbers example: range(1,5) contains 1 to 4 numbers, the last number is excluded\n",
    "#list function is used to create list example: list(1,2,3)\n",
    "# below we craete a list of range 1 to 5 (excluding 5)\n",
    "\n",
    "c=list(range(1,5))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[1, 2, 3, 4]\n"
     ]
    }
   ],
   "source": [
    "print(c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "2\n",
      "3\n",
      "4\n"
     ]
    }
   ],
   "source": [
    "#range can also be used in for loop\n",
    "\n",
    "for i in range(1,5):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "10\n"
     ]
    }
   ],
   "source": [
    "#to get sum of 4 numbers\n",
    "#shorthand operator += used for addition\n",
    "total2=0\n",
    "for i in range(1,5):\n",
    "    total2+=i\n",
    "print(total2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[1, 2, 3, 4, 5, 6, 7]\n"
     ]
    }
   ],
   "source": [
    "print(list(range(1,8)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n"
     ]
    }
   ],
   "source": [
    "#modulo operator-gives reminder after division of 2 numbers\n",
    "print(4%3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n"
     ]
    }
   ],
   "source": [
    "print(5%3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0\n"
     ]
    }
   ],
   "source": [
    "print(6%3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "9\n"
     ]
    }
   ],
   "source": [
    "#sum of elements that are multiple of 3\n",
    "total3=0\n",
    "for i in range(1,8):\n",
    "    if i%3 == 0:\n",
    "        total3+=i\n",
    "print(total3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]\n"
     ]
    }
   ],
   "source": [
    "#compute all multiples of 3,5 in the range of 1 to 100\n",
    "\n",
    "print(list(range(1,100)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "3\n",
      "5\n",
      "6\n",
      "9\n",
      "10\n",
      "12\n",
      "15\n",
      "18\n",
      "20\n",
      "21\n",
      "24\n",
      "25\n",
      "27\n",
      "30\n",
      "33\n",
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      "39\n",
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      "60\n",
      "63\n",
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      "84\n",
      "85\n",
      "87\n",
      "90\n",
      "93\n",
      "95\n",
      "96\n",
      "99\n"
     ]
    }
   ],
   "source": [
    "for i in range(1,100):\n",
    "    if((i%3==0) or (i%5==0)):\n",
    "        print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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