3. Control flow.ipynb

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   "source": [
    "# Control flow statements"
   ]
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   "source": [
    "# 1. Conditional statements"
   ]
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   "source": [
    "![](images/conditional.png)"
   ]
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    "### Challenge:\n",
    "[Python If-Else](https://www.hackerrank.com/challenges/py-if-else)"
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   "source": [
    "## Nested if-else\n",
    "\n",
    "Write a python program to input an integer from user and print:\n",
    "- -1 if integer is negative.\n",
    "- 0 if integer is zero.\n",
    "- 1 if integer is positive.\n",
    "\n",
    "What's not cool with this approach???\n",
    "\n",
    "```python\n",
    "if x < 0:\n",
    "   sign = -1\n",
    "if x == 0\n",
    "   sign = 0\n",
    "if x > 0\n",
    "   sign = 1\n",
    "```\n",
    "\n",
    "![](images/nested.jpeg)"
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    "# 2. Looping statements"
   ]
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   "source": [
    "## (i) while\n",
    "\n",
    "The while statement allows you to repeatedly execute a block of statements as long as a condition is true.\n",
    "\n",
    "![](images/while-loop.png)"
   ]
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    "## (ii) for\n",
    "\n",
    "The for..in statement is another looping statement which iterates over a sequence of objects i.e. go through each item in a sequence.\n",
    "\n",
    "![](images/for_loop.jpg)"
   ]
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   "source": [
    "### Challenge:\n",
    "Solve using **for** as well as **while** loop:\n",
    "[Loops](https://www.hackerrank.com/challenges/python-loops)"
   ]
  },
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   "source": [
    "## Infinite loops\n",
    "\n",
    "Beware!\n",
    "\n",
    "![](images/infinite.jpg)"
   ]
  },
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   "source": [
    "## Nested loops\n",
    "\n",
    "Yes! Loops can also be nested.\n",
    "\n",
    "Lets do matrix addition!"
   ]
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   "source": [
    "### Challenge for you!\n",
    "\n",
    "Given an integer n, print a nXn matrix with squares (outermost to innermost) having values n, then n-1 and so on.\n",
    "For example, given 5, output is:\n",
    "```\n",
    "5 5 5 5 5\n",
    "5 4 4 4 5\n",
    "5 4 3 4 5\n",
    "5 4 4 4 5 \n",
    "5 5 5 5 5\n",
    "```"
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   "source": [
    "## break, continue and pass"
   ]
  },
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   "source": [
    "![](images/break.jpg)"
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