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   "source": [
    "# Contiguous Subarray\n",
    "Largest Sum Contiguous Subarray"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Kadane's Algorithm - Dynamic Programming - O(n)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": true
   },
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   "source": [
    "def largeSumContiguousSubArr(arr):\n",
    "    start, end = 0, 0\n",
    "    s = 0\n",
    "    max_so_far, curr_max = 0, 0\n",
    "    \n",
    "    for i in range(len(arr)):\n",
    "        curr_max += arr[i]\n",
    "        \n",
    "        if curr_max < 0:\n",
    "            curr_max = 0\n",
    "            s = i + 1\n",
    "        elif curr_max > max_so_far:\n",
    "            max_so_far = curr_max\n",
    "            start = s\n",
    "            end = i\n",
    "            \n",
    "    return arr[start : end + 1], max_so_far"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[-2, -3, 4, -1, -2, 1, 5, -3]"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "arr = [-2, -3, 4, -1, -2, 1, 5, -3]\n",
    "arr"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "([4, -1, -2, 1, 5], 7)"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "largeSumContiguousSubArr(arr)"
   ]
  }
 ],
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