From c75679e94a1c4c13781169c2df6559f337be2c2f Mon Sep 17 00:00:00 2001
From: Peter Norvig <peter@norvig.com>
Date: Mon, 1 Jan 2018 16:41:46 -0800
Subject: [PATCH] Countdown.ipynb updated with Littman Countdown

---
 ipynb/Countdown.ipynb | 52 ++++++++++++++++++++++++-------------------
 1 file changed, 29 insertions(+), 23 deletions(-)

diff --git a/ipynb/Countdown.ipynb b/ipynb/Countdown.ipynb
index dc61328..a756429 100644
--- a/ipynb/Countdown.ipynb
+++ b/ipynb/Countdown.ipynb
@@ -2876,16 +2876,16 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 75,
+   "execution_count": 80,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "'2.0+(1*8), 2.0-(1-8), (2.0-1)*8, (2*0)-(1-8), √(2.0*18), -2.0-(1-8), √(-2.0+18), 2.0+(1^8), 20-18, 2.0-(1^8)'"
+       "'2.0+(1*8), 2.0-(1-8), (2.0-1)*8, (2*0)-(1-8), √(2.0*18), -2.0-(1-8), √(-2.0+18), 2.0+(1^8), 20-18, 2.0-(1^8), 2*(0/18)'"
       ]
      },
-     "execution_count": 75,
+     "execution_count": 80,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -2896,7 +2896,7 @@
     "\n",
     "def littman_countdown(year):\n",
     "    \"Return a Littman countdown for the year.\"\n",
-    "    return ', '.join(littman(year, i) for i in range(10, 0, -1))\n",
+    "    return ', '.join(littman(year, i) for i in range(10, -1, -1))\n",
     "\n",
     "def littman(year, i):\n",
     "    \"Return a string that makes i with the digits of year.\"\n",
@@ -2917,31 +2917,37 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 76,
+   "execution_count": 82,
    "metadata": {},
    "outputs": [
     {
-     "data": {
-      "text/plain": [
-       "{2011: '20/(1+1), 20-11, -2.0+(1/.1), (2.0+1)!+1, √(20-11)!, (2.0+1)!-1, 2.0*(1+1), √(20-11), 2+(0/11), 2.0/(1+1)',\n",
-       " 2012: '20/(1*2), (2.0+1)^2, 20-12, 2.0+(1/.2), 2.0*(1+2), 2.0+(1+2), 2.0*(1*2), 2.0-(1-2), 2+(0/12), -.20+1.2',\n",
-       " 2013: '20/(-1+3), (2.0+1)*3, 2.0*(1+3), 20-13, 2.0+(1+3), 20/(1+3), 2.0-(1-3), (2.0-1)*3, 2+(0/13), (2.0+1)/3',\n",
-       " 2014: '2.0*(1+4), (2.0+1)^√4, 2.0/(1/4), 2.0+(1+4), 20-14, 20*(1/4), 20/(1+4), -20-(1-4!), 2+(0/14), .20*(1+4)',\n",
-       " 2015: '2.0*(1*5), √(201-5!), 2.0+(1+5), 2.0+(1*5), (.20*15)!, 20-15, 20/(1*5), .20*15, 2+(0/15), 2*(0.1*5)',\n",
-       " 2016: '2*(0-(1-6)), 2.0+(1+6), 2.0*√16, 2.0-(1-6), √(20+16), 20/√16, 20-16, 2.0+(1^6), 2+(0/16), .20*(-1+6)',\n",
-       " 2017: '2.0+(1+7), 2.0+(1*7), 2.0-(1-7), (2.0-1)*7, (20-17)!, -2.0+(1*7), -2.0-(1-7), 20-17, 2+(0/17), 2.0-(1^7)',\n",
-       " 2018: '2.0+(1*8), 2.0-(1-8), (2.0-1)*8, (2*0)-(1-8), √(2.0*18), -2.0-(1-8), √(-2.0+18), 2.0+(1^8), 20-18, 2.0-(1^8)',\n",
-       " 2019: '20-(1+9), (2.0-1)*9, (2*0)-(1-9), -2.0+(1*9), -2.0-(1-9), 20/(1+√9), 2.0-(1-√9), 2.0+(1^9), 2+(0/19), 20-19'}"
-      ]
-     },
-     "execution_count": 76,
-     "metadata": {},
-     "output_type": "execute_result"
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "2011:\n",
+      "20/(1+1), 20-11, -2.0+(1/.1), (2.0+1)!+1, √(20-11)!, (2.0+1)!-1, 2.0*(1+1), √(20-11), 2+(0/11), 2.0/(1+1), 2*(0/11)\n",
+      "2012:\n",
+      "20/(1*2), (2.0+1)^2, 20-12, 2.0+(1/.2), 2.0*(1+2), 2.0+(1+2), 2.0*(1*2), 2.0-(1-2), 2+(0/12), -.20+1.2, 2*(0/12)\n",
+      "2013:\n",
+      "20/(-1+3), (2.0+1)*3, 2.0*(1+3), 20-13, 2.0+(1+3), 20/(1+3), 2.0-(1-3), (2.0-1)*3, 2+(0/13), (2.0+1)/3, 2*(0/13)\n",
+      "2014:\n",
+      "2.0*(1+4), (2.0+1)^√4, 2.0/(1/4), 2.0+(1+4), 20-14, 20*(1/4), 20/(1+4), -20-(1-4!), 2+(0/14), .20*(1+4), 2*(0/14)\n",
+      "2015:\n",
+      "2.0*(1*5), √(201-5!), 2.0+(1+5), 2.0+(1*5), (.20*15)!, 20-15, 20/(1*5), .20*15, 2+(0/15), 2*(0.1*5), 2*(0/15)\n",
+      "2016:\n",
+      "2*(0-(1-6)), 2.0+(1+6), 2.0*√16, 2.0-(1-6), √(20+16), 20/√16, 20-16, 2.0+(1^6), 2+(0/16), .20*(-1+6), 2*(0/16)\n",
+      "2017:\n",
+      "2.0+(1+7), 2.0+(1*7), 2.0-(1-7), (2.0-1)*7, (20-17)!, -2.0+(1*7), -2.0-(1-7), 20-17, 2+(0/17), 2.0-(1^7), 2*(0/17)\n",
+      "2018:\n",
+      "2.0+(1*8), 2.0-(1-8), (2.0-1)*8, (2*0)-(1-8), √(2.0*18), -2.0-(1-8), √(-2.0+18), 2.0+(1^8), 20-18, 2.0-(1^8), 2*(0/18)\n",
+      "2019:\n",
+      "20-(1+9), (2.0-1)*9, (2*0)-(1-9), -2.0+(1*9), -2.0-(1-9), 20/(1+√9), 2.0-(1-√9), 2.0+(1^9), 2+(0/19), 20-19, 2*(0/19)\n"
+     ]
     }
    ],
    "source": [
-    "{y: littman_countdown(y) \n",
-    " for y in range(2011, 2020)}"
+    "for y in range(2011, 2020):\n",
+    "    print('{}:\\n{}'.format(y, littman_countdown(y)))"
    ]
   }
  ],