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wingfishwingfish
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2016.12.12 edit lesson 3 notebook
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‎python_basic/python_basic_lesson_03.ipynb‎

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@@ -6,7 +6,7 @@
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"source": [
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"# Lesson 3\n",
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"\n",
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"Python Basic, Lesson 2, v1.0.0, 2016.12 by David.Yi\n",
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"Python Basic, Lesson 3, v1.0.0, 2016.12 by David.Yi\n",
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"\n",
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"\n",
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"### 上次内容要点\n",
@@ -22,7 +22,7 @@
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" \n",
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"### 本次内容要点\n",
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"\n",
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"* list 的切片用法\n",
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"* 列表的切片用法\n",
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"* 函数用法\n",
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"* 程序练习：剪刀石头布、猜数游戏\n"
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]
@@ -33,18 +33,32 @@
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"source": [
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"### 列表切片\n",
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"\n",
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"a[start:end] # 从start开始到end-1结束 \n",
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"列表切片的语法\n",
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"\n",
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"a[start:] # 从start开始直到末尾\n",
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"a[start:end] 从start开始到end-1结束 \n",
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"\n",
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"a[:end] # 从头部开始直到end结束\n",
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"a[start:] 从start开始直到末尾\n",
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"\n",
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"a[:] # 复制整个列表\n"
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"a[:end] 从头部开始直到end结束\n",
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"\n",
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"a[:] 复制整个列表\n",
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"\n",
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"从左到右时候的位置关系\n",
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"\n",
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" +---+---+---+---+---+---+\n",
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" | P | y | t | h | o | n |\n",
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" +---+---+---+---+---+---+\n",
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" 0 1 2 3 4 5 6\n",
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"-6 -5 -4 -3 -2 -1\n",
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"\n",
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"a[start:end:step] step 表示步长，正负号表示方向\n",
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"step 默认为 +1 ，所以默认 start 和 end 是从头到尾，如果 step 为负数，则 start 表示尾，end 表示头。\n",
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"start 和 end 是根据 step 来确认的。"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 9,
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"execution_count": 40,
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"metadata": {
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"collapsed": false
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},
@@ -64,14 +78,16 @@
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"print(a)\n",
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"\n",
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"b = a[0:3]\n",
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"\n",
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"# 省略start，表示从头开始\n",
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"c = a[:3]\n",
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"print(b)\n",
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"print(c)"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 10,
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"execution_count": 41,
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"metadata": {
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"collapsed": false
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},
@@ -85,6 +101,7 @@
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}
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],
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"source": [
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"# 省略 end，从-1 到 end\n",
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"b = a[-1:]\n",
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"print(b)"
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]
@@ -111,7 +128,7 @@
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},
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{
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"cell_type": "code",
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"execution_count": 15,
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"execution_count": 43,
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"metadata": {
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"collapsed": false
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},
@@ -136,7 +153,7 @@
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},
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{
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"cell_type": "code",
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"execution_count": 16,
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"execution_count": 46,
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"metadata": {
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"collapsed": false
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},
@@ -156,7 +173,7 @@
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},
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{
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"cell_type": "code",
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"execution_count": 17,
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"execution_count": 47,
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"metadata": {
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"collapsed": false
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},
@@ -176,7 +193,28 @@
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},
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{
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"cell_type": "code",
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"execution_count": 18,
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"execution_count": 48,
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"metadata": {
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"collapsed": false
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},
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"outputs": [
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{
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"name": "stdout",
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"output_type": "stream",
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"text": [
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"[]\n"
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]
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}
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],
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"source": [
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"# step 错误，不输出结果\n",
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"b = a[0:10:-2]\n",
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"print(b)"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 49,
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"metadata": {
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"collapsed": false
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},
@@ -196,7 +234,7 @@
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},
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{
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"cell_type": "code",
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"execution_count": 19,
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"execution_count": 52,
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"metadata": {
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"collapsed": false
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},
@@ -214,6 +252,26 @@
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"print(b)"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 53,
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"metadata": {
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"collapsed": false
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},
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"outputs": [
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{
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"name": "stdout",
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"output_type": "stream",
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"text": [
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"[99, 98, 97, 96, 95]\n"
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]
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}
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],
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"source": [
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"b = a[-1:-6:-1]\n",
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"print(b)"
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]
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},
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{
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"cell_type": "code",
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"execution_count": 20,
@@ -261,6 +319,8 @@
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}
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],
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"source": [
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"# 列表反转\n",
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"\n",
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"a = ['Shanghai', 'Beijing', 'Hangzhou', 'Tokyo', 'Osaka']\n",
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"a.reverse()\n",
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"print(a)"
@@ -282,7 +342,8 @@
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}
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],
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"source": [
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"# use slice replace reverse\n",
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"# 使用切片来完成反转\n",
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"\n",
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"a = ['Shanghai', 'Beijing', 'Hangzhou', 'Tokyo', 'Osaka']\n",
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"b = a[::-1]\n",
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"print(b)"
@@ -306,7 +367,7 @@
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}
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],
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"source": [
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"# string slice like list\n",
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"# 字符串切片操作类似列表\n",
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"a = 'abcdefghi'\n",
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"print(a[1:2])\n",
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"print(a[3:5])\n",
@@ -551,17 +612,28 @@
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"写一个函数，输入一个数字，判断其是否是偶数，是偶数的话，返回 True，反之返回 False\n",
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"写一个函数，输入一个英文单词，返回其中的元音字母的个数"
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"---\n",
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"\n",
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"* 写一个函数，输入一个数字，判断其是否是偶数，是偶数的话，返回 True，反之返回 False\n",
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"* 写一个函数，输入一个英文单词，返回其中的元音字母的个数"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"execution_count": 54,
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"metadata": {
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"collapsed": true
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"collapsed": false
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},
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"outputs": [],
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"outputs": [
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{
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"name": "stdout",
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"output_type": "stream",
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"text": [
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"Please input a number:14\n",
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"这是个偶数\n"
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]
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}
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],
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"source": [
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"a = int(input('Please input a number:'))\n",
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"\n",
@@ -573,11 +645,20 @@
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"execution_count": 55,
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"metadata": {
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"collapsed": true
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"collapsed": false
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},
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"outputs": [],
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"outputs": [
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{
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"name": "stdout",
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"output_type": "stream",
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"text": [
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"plese input a word:elephant\n",
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"3\n"
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]
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}
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],
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"source": [
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"a = input('plese input a word:')\n",
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"b = ['a','e','i','o','u']\n",

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