37 lines
929 B
D
37 lines
929 B
D
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module day2.part2.main;
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import std;
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void main()
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{
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const passwords = slurp!(size_t, size_t, char, string)("input", "%s-%s %s: %s");
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passwords.findNumberOfValidPasswords.writeln;
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}
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alias PasswordWithPolicy = Tuple!(size_t, size_t, char, string);
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ulong findNumberOfValidPasswords(const PasswordWithPolicy[] passwords)
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{
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return passwords.filter!(password => password.isPasswordValid).count;
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}
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bool isPasswordValid(const PasswordWithPolicy password)
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{
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immutable pos1 = password[0] - 1;
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immutable pos2 = password[1] - 1;
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immutable character = password[2];
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immutable actualPassword = password[3];
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return (actualPassword[pos1] == character) != (actualPassword[pos2] == character);
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}
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unittest
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{
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immutable input = [
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tuple(1UL, 3UL, 'a', "abcde"),
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tuple(1UL, 3UL, 'b', "cdefg"),
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tuple(2UL, 9UL, 'c', "ccccccccc")
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];
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assert(input.findNumberOfValidPasswords == 1);
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}
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