15 lines
594 B
D
15 lines
594 B
D
void main() @safe {
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import std.stdio, std.range, std.algorithm, std.typecons, std.numeric;
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enum triples = (in uint n) pure nothrow @safe /*@nogc*/ =>
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iota(1, n + 1)
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.map!(z => iota(1, z + 1)
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.map!(x => iota(x, z + 1).map!(y => tuple(x, y, z))))
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.joiner.joiner
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.filter!(t => t[0] ^^ 2 + t[1] ^^ 2 == t[2] ^^ 2 && t[].only.sum <= n)
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.map!(t => tuple(t[0 .. 2].gcd == 1, t[]));
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auto xs = triples(100);
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writefln("\nUp to %d there are %d triples, %d are primitive.", N, xs.count,
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xs.filter!q{ a[0] }.count);
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}
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