2023312216_박균호.ipynb

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        "## Task\n",
        "- Complete **isHappy** function following the description below\n",
        "\n",
        "### Happy Number\n",
        "Write an algorithm to determine if a number **n** is happy.\n",
        "\n",
        "A **happy number** is a number defined by the following process:\n",
        "\n",
        "* Starting with any positive integer, replace the number by the sum of the squares of its digits.\n",
        "* Repeat the process until the number equals 1 (where it will stay), or it **loops endlessly in a cycle** which does not include 1.\n",
        "* Those numbers for which this process **ends in 1** are happy.\n",
        "\n",
        "Return **true** if n is a happy number, and **false** if not.\n",
        "\n",
        "Constraints:\n",
        "1 <= n <= $2^{31}$ - 1"
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            "2\n",
            "False\n"
          ]
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      "source": [
        "def isHappy(n):\n",
        "  numList = []\n",
        "  n1 = n\n",
        "  sum = 0\n",
        "  while (n!=1):\n",
        "    while(n1 != 0):\n",
        "      sum += (n1 %10)**2\n",
        "      n1 = n1//10\n",
        "\n",
        "    if sum in numList:\n",
        "      return False\n",
        "    else:\n",
        "      numList.append(sum)\n",
        "    n = sum\n",
        "    n1 = sum\n",
        "    sum = 0\n",
        "  return True\n",
        "\n",
        "num = int(input())\n",
        "print (isHappy(num))\n"
      ]
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      "source": [
        "**Testcase 1.**\n",
        "\n",
        "**Input**: 19\n",
        "\n",
        "**Output**: True\n",
        "\n",
        "**Explanation**:\n",
        "\n",
        "$1^2 + 9^2 = 82$\n",
        "\n",
        "$8^2 + 2^2 = 68$\n",
        "\n",
        "$6^2 + 8^2 = 100$\n",
        "\n",
        "$1^2 + 0^2 + 0^2 = 1$"
      ],
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      "source": [
        "**Testcase 2.**\n",
        "\n",
        "**Input**: 2\n",
        "\n",
        "**Output**: False"
      ],
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