５人の学生を 身長・体重で ソート (関数ポインタ)

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５人の学生を 身長・体重で ソート (関数ポインタ)

Ruby

NINSU = 5

def compare_height(x, y)
    return  1 if (x["height"] > y["height"])
    return -1 if (x["height"] < y["height"])
    return 0
end

def compare_weight(x, y)
    return  1 if (x["weight"] > y["weight"])
    return -1 if (x["weight"] < y["weight"])
    return 0
end

def sort(data, n, compare)
    k = n - 1
    while (k >= 0)
        j = -1
        for i in 1..k
            if (compare.call(data[i - 1], data[i]) > 0)
                j = i - 1
                data[i], data[j] = data[j], data[i]
            end
        end
        k = j
    end
end

data =  [
        {"name" => "Sato",   "height" => 178, "weight" => 61.0},
        {"name" => "Sanaka", "height" => 175, "weight" => 60.5},
        {"name" => "Takao",  "height" => 173, "weight" => 80.0},
        {"name" => "Mike",   "height" => 165, "weight" => 72.0},
        {"name" => "Masaki", "height" => 179, "weight" => 77.5}
        ]
        
puts "ソート前："
data.each_with_index do |d, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, d["name"], d["height"], d["weight"])
end
puts ""

sort(data, NINSU, method(:compare_height))

puts "身長でソート後："
data.each_with_index do |d, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, d["name"], d["height"], d["weight"])
end
puts ""

sort(data, NINSU, method(:compare_weight))

puts "体重でソート後："
data.each_with_index do |d, i|
    printf("%2d:%-8s%4d%6.1f\n", i + 1, d["name"], d["height"], d["weight"])
end

実行結果

L:\>ruby  l:\lesson_12_097.rb

メ[ト前：

 1:Sato     178  61.0

 2:Sanaka   175  60.5

 3:Takao    173  80.0

 4:Mike     165  72.0

 5:Masaki   179  77.5
身長でメ[ト後：

 1:Mike     165  72.0

 2:Takao    173  80.0

 3:Sanaka   175  60.5

 4:Sato     178  61.0

 5:Masaki   179  77.5
体重でメ[ト後：

 1:Sanaka   175  60.5

 2:Sato     178  61.0

 3:Mike     165  72.0

 4:Masaki   179  77.5

 5:Takao    173  80.0