pushing learn to program exercises

SamGerber · SamGerber · commit 8696e72e58ce · 2015-11-01T00:34:49.000Z
diff --git a/pre-course/learn_to_program/01-chapter_2_numbers/00-hours_in_year.rb b/pre-course/learn_to_program/01-chapter_2_numbers/00-hours_in_year.rb
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+# Learn to Program - Second Edition
+# Exercise from Chapter 2 - Numbers
+# Sam Gerber
+
+# Write a program that tells you how many hours are in a year
+
+def hours_in_year(year)
+  hours = 365 * 24
+  hours += 24 if year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)
+  hours
+end
+
+puts hours_in_year 1900 # =>8760
+puts hours_in_year 2000 # =>8784
+puts hours_in_year 2001 # =>8760
+puts hours_in_year 2004 # =>8784
diff --git a/pre-course/learn_to_program/01-chapter_2_numbers/01-minutes_in_a_decade.rb b/pre-course/learn_to_program/01-chapter_2_numbers/01-minutes_in_a_decade.rb
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+# Learn to Program - Second Edition
+# Exercise from Chapter 2 - Numbers
+# Sam Gerber
+
+# Write a program that tells you how many minutes are in a decade
+
+def minutes_in_decade(start_year = 1900)
+  days = 0
+  start_year.step.take(10).each do |year|
+    days += 365
+    days += 1 if year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)
+  end
+  days * 24 * 60 * 60
+end
+
+puts minutes_in_decade 1897 # =>315446400
+puts minutes_in_decade 2000 # =>315619200
+puts minutes_in_decade 2001 # =>315532800
+puts minutes_in_decade 2004 # =>315619200
diff --git a/pre-course/learn_to_program/01-chapter_2_numbers/02-your_age_in_seconds.rb b/pre-course/learn_to_program/01-chapter_2_numbers/02-your_age_in_seconds.rb
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+# Learn to Program - Second Edition
+# Exercise from Chapter 2 - Numbers
+# Sam Gerber
+
+# Write a program that tells you your age in seconds
+
+def age_in_seconds(day, month, year)
+  birthday = Time.local(year, month, day)
+  Time.new - birthday
+end
+
+puts age_in_seconds(31, 12, 1987) # => 877_000_000
diff --git a/pre-course/learn_to_program/01-chapter_2_numbers/03-our_dear_authors_age.rb b/pre-course/learn_to_program/01-chapter_2_numbers/03-our_dear_authors_age.rb
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+# Learn to Program - Second Edition
+# Exercise from Chapter 2 - Numbers
+# Sam Gerber
+
+# If I am 1_160 million seconds old, how old am I?
+
+def age_in_years(seconds)
+  birthday = Time.new - seconds
+  Time.new.year - birthday.year
+end
+
+puts age_in_years(1_160_000_000) # => 877_000_000
diff --git a/pre-course/learn_to_program/01-chapter_2_numbers/examples.rb b/pre-course/learn_to_program/01-chapter_2_numbers/examples.rb
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+# Learn to Program - Second Edition
+# Examples from book
+# Sam Gerber
+
+# Chapter 2 - Numbers
+
+puts 1 + 2 # => 3
+
+# 2.4 Simple Arithmetic
+puts 1.0 + 2.0 # => 3.0
+puts 2.0 * 3.0 # => 6.0
+puts 5.0 - 8.0 # => -3.0
+puts 9.0 / 2.0 # => 4.5
+
+puts 1 + 2 # => 3
+puts 2 * 3 # => 6
+puts 5 - 8 # => -3
+puts 9 / 2 # => 4
+
+puts 5 * (12-8) + -15             # =>5
+puts 98 + (59872 / (13*8)) * -51  # =>-29227
