46 lines
973 B
Ruby
46 lines
973 B
Ruby
# The is_bad_version API is already defined for you.
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# @param {Integer} version
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# @return {boolean} whether the version is bad
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# def is_bad_version(version):
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# @param {Integer} n
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# @return {Integer}
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def first_bad_version(n)
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left = 1
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right = n
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while left < right do
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mid = (left + right).div(2)
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if is_bad_version(mid) then
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right = mid
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else
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left = mid + 1
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end
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end
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return left
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end
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RSpec.describe "first_bad_version" do
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it "n = 5, bad = 4" do
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def is_bad_version(n)
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return n >= 4
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end
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expect(first_bad_version(5)).to eq(4)
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end
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it "n = 1, bad = 1" do
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def is_bad_version(n)
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return n >= 1
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end
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expect(first_bad_version(1)).to eq(1)
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end
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it "n = 1000000, bad = 76192" do
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def is_bad_version(n)
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return n >= 76192
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end
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expect(first_bad_version(1000000)).to eq(76192)
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end
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end
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