Python - Storing Data Using Other Collection Types(set, add method, len function(built-in function))

Practical Programming
An Introduction to Computer Science
Using Python 3
(Pragmatic Programmers)
(Pragmatic Bookshelf)
Paul Gries (著) Jennifer Campbell (著)
Jason Montojo (著) Lynn Beighley (編集)

開発環境

• OS X Mavericks - Apple(OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python 3.4 (プログラミング言語)

Practical Programming: An Introduction to Computer Science Using Python 3 (Pragmatic Programmers) (Paul Gries (著)、Jennifer Campbell (著)、Jason Montojo (著)、Lynn Beighley (編集)、Pragmatic Bookshelf)のChapter 11(Storing Data Using Other Collection Types)、11.8(Exercises) 6.を解いてみる。

11.8(Exercises) 6.

コード(BBEdit)

sample6.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

def countDuplicates(d):
    values = d.values()
    s1 = set()
    s2 = set()
    for value in values:
        if value in s1:
            s2.add(value)
        else:
            s1.add(value)
    return len(s2)

d1 = dict(a=1, b=2, c=1, d=3, e=4)
d2 = dict(a=1, b=2, c=1, d=2, e=3)
d3 = dict(a=1, b=2, c=3, d=4, e=5)
d4 = dict(a=1, b=2, c=2, d=2, e=3)

for d in [d1, d2, d3, d4]:
    print(countDuplicates(d))

入出力結果(Terminal, IPython)

$ ./sample6.py
1
2
0
1
$