Add for + unpacking, start dictionary

Author: yammesicka

week4/1_For_Loops.ipynb

@@ -781,6 +781,237 @@
     "</div>"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### <span style=\"text-align: right; direction: rtl; float: right;\">מבנים מורכבים</span>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "הרשימה הבאה מכילה tupleים בגודל 2 איברים:\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 91,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "words = [('star', 'rats'), ('wolf', 'flow'), ('racecar', 'racecar'), ('ekans', 'snake')]"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<div class=\"align-center\" style=\"display: flex; text-align: right; direction: rtl; clear: both;\">\n",
+    "    <div style=\"display: flex; width: 10%; float: right; clear: both;\">\n",
+    "        <img src=\"images/exercise.svg\" style=\"height: 50px !important;\" alt=\"תרגול\"> \n",
+    "    </div>\n",
+    "    <div style=\"width: 70%\">\n",
+    "        <p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "            כתבו לולאת <code>for</code> שתדפיס עבור כל זוג מחרוזות ברשימה: <samp dir=\"ltr\" style=\"direction: ltr\">Reverse \"X\" to get \"Y\"</samp>.<br>\n",
+    "            לדוגמה, עבור הזוג האחרון מתוך 4 הזוגות, היא תדפיס: <samp dir=\"ltr\" style=\"direction: ltr\">Reverse \"ekans\" to get \"snake\"</samp>.\n",
+    "        </p>\n",
+    "    </div>\n",
+    "    <div style=\"display: flex; width: 20%; border-right: 0.1rem solid #A5A5A5; padding: 1rem 2rem;\">\n",
+    "        <p style=\"text-align: center; direction: rtl; justify-content: center; align-items: center; clear: both;\">\n",
+    "            <strong>חשוב!</strong><br>\n",
+    "            פתרו לפני שתמשיכו!\n",
+    "        </p>\n",
+    "    </div>\n",
+    "</div>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "על־מנת לפתור את התרגיל, כתבתם קוד שהשתמש במיקום של הערך הראשון (0) ושל הערך השני (1).<br>\n",
+    "הנה דוגמה לצורה שבה אני פתרתי אותו:\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 105,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Reverse \"star\" to get \"rats\".\n",
+      "Reverse \"wolf\" to get \"flow\".\n",
+      "Reverse \"racecar\" to get \"racecar\".\n",
+      "Reverse \"ekans\" to get \"snake\".\n"
+     ]
+    }
+   ],
+   "source": [
+    "for word_and_reversed_word in words:\n",
+    "    word = word_and_reversed_word[0]\n",
+    "    reversed_word = word_and_reversed_word[1]\n",
+    "    print(f'Reverse \"{word}\" to get \"{reversed_word}\".')"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "נראה דרך נוספת לפתור את התרגיל, רק שהפעם נשתמש בטריק שנקרא <dfn>unpacking</dfn> (או \"<dfn>פירוק</dfn>\").<br>\n",
+    "מכיוון שכל tuple ברשימת <var>words</var> מכיל 2 איברים, נוכל לתת להם שמות כבר בראש הלולאה ולחלץ אותם מה־tuple:\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 102,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Reverse \"star\" to get \"rats\".\n",
+      "Reverse \"wolf\" to get \"flow\".\n",
+      "Reverse \"racecar\" to get \"racecar\".\n",
+      "Reverse \"ekans\" to get \"snake\".\n"
+     ]
+    }
+   ],
+   "source": [
+    "for word, reversed_word in words:\n",
+    "    print(f'Reverse \"{word}\" to get \"{reversed_word}\".')"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "בכל חזרור של הלולאה שכתובה למעלה, ה־<code>for</code> יעבור על tuple בודד, בדיוק כמו שקרה עד עכשיו.<br>\n",
+    "השינוי הוא שבמקום שה־tuple ישמר כמו שהוא במשתנה בודד שהוגדר בראש הלולאה, הערכים שבו \"יחולצו\" למשתנים בראש הלולאה.<br>\n",
+    "זה יכול לעבוד מכיוון שבראש הלולאה כתבנו מספר משתנים שזהה למספר הערכים בכל tuple.\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<p style=\"text-align: right; direction: rtl; float: right; clear: both;\">\n",
+    "לפניכם תרשים המתאר את תוכן המשתנה <var>words</var>.<br>\n",
+    "הטבלה הגדולה מייצגת את הרשימה <var>words</var>, וכל אחת מהטבלאות הקטנות מייצגת tuple בתוך הרשימה.<br>\n",
+    "בכל חזרור של ה־<code>for</code> המופיע למעלה, המשתנה <var>word</var> יקבל ערך שמסומן באדום, והמשתנה <var>reversed_word</var> יקבל את הערך הירוק התואם. \n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "<table style=\"font-size: 1.5rem; border: 0px solid black; border-spacing: 0px;\">\n",
+    "    <caption style=\"direction: rtl; text-align: center;\">תצוגה על המשתנה <var>words</var> ועל צורת הפירוק שלו</caption>\n",
+    "    <tr>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-bottom: 1px solid;\">0</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">1</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">2</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">3</td>\n",
+    "    </tr>\n",
+    "    <tbody>\n",
+    "        <tr>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid;\">\n",
+    "<table style=\"font-size: 1.5rem; border: 0px solid black; border-spacing: 0px;\">\n",
+    "    <tr>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-bottom: 1px solid;\">0</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">1</td>\n",
+    "    </tr>\n",
+    "    <tbody>\n",
+    "        <tr>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #FF8578;\">\"star\"</td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #98FB98;\">\"rats\"</td>\n",
+    "        </tr>\n",
+    "        <tr style=\"background: #f5f5f5;\">\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right;\">-2</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-1</td>\n",
+    "        </tr>\n",
+    "    </tbody>\n",
+    "</table>\n",
+    "            </td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid;\">\n",
+    "<table style=\"font-size: 1.5rem; border: 0px solid black; border-spacing: 0px;\">\n",
+    "    <tr>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-bottom: 1px solid;\">0</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">1</td>\n",
+    "    </tr>\n",
+    "    <tbody>\n",
+    "        <tr>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #FF8578;\">\"wolf\"</td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #98FB98;\">\"flow\"</td>\n",
+    "        </tr>\n",
+    "        <tr style=\"background: #f5f5f5;\">\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right;\">-2</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-1</td>\n",
+    "        </tr>\n",
+    "    </tbody>\n",
+    "</table>            \n",
+    "            </td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid;\">\n",
+    "<table style=\"font-size: 1.5rem; border: 0px solid black; border-spacing: 0px;\">\n",
+    "    <tr>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-bottom: 1px solid;\">0</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">1</td>\n",
+    "    </tr>\n",
+    "    <tbody>\n",
+    "        <tr>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #FF8578;\">\"racecar\"</td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #98FB98;\">\"racecar\"</td>\n",
+    "        </tr>\n",
+    "        <tr style=\"background: #f5f5f5;\">\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right;\">-2</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-1</td>\n",
+    "        </tr>\n",
+    "    </tbody>\n",
+    "</table>\n",
+    "            </td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid;\">\n",
+    "<table style=\"font-size: 1.5rem; border: 0px solid black; border-spacing: 0px;\">\n",
+    "    <tr>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-bottom: 1px solid;\">0</td>\n",
+    "        <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777;  text-align: left; border-left: 1px solid #555555; border-bottom: 1px solid;\">1</td>\n",
+    "    </tr>\n",
+    "    <tbody>\n",
+    "        <tr>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #FF8578;\">\"ekans\"</td>\n",
+    "            <td style=\"padding-top: 8px; padding-bottom: 8px; padding-left: 10px; padding-right: 10px; vertical-align: bottom; border: 2px solid; background-color: #98FB98;\">\"snake\"</td>\n",
+    "        </tr>\n",
+    "        <tr style=\"background: #f5f5f5;\">\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right;\">-2</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-1</td>\n",
+    "        </tr>\n",
+    "    </tbody>\n",
+    "</table>\n",
+    "            </td>\n",
+    "        </tr>\n",
+    "        <tr style=\"background: #f5f5f5;\">\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right;\">-4</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-3</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-2</td>\n",
+    "            <td style=\"padding-left: 4px; padding-top: 2px; padding-bottom: 3px; font-size: 1.3rem; color: #777; text-align: right; border-left: 1px solid #555555;\">-1</td>\n",
+    "        </tr>\n",
+    "    </tbody>\n",
+    "</table>"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},