48 lines
1.0 KiB
D
48 lines
1.0 KiB
D
import std.stdio, std.conv;
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struct Number(T) {
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T x; // base
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alias x this;
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string toString() const { return text(x); }
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Number opBinary(string op)(in int exponent)
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const pure nothrow @nogc if (op == "^^") in {
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if (exponent < 0)
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assert (x != 0, "Division by zero");
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} body {
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debug puts("opBinary ^^");
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int zerodir;
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T factor;
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if (exponent < 0) {
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zerodir = +1;
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factor = T(1) / x;
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} else {
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zerodir = -1;
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factor = x;
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}
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T result = 1;
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int e = exponent;
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while (e != 0)
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if (e % 2 != 0) {
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result *= factor;
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e += zerodir;
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} else {
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factor *= factor;
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e /= 2;
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}
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return Number(result);
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}
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}
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void main() {
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alias Double = Number!double;
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writeln(Double(2.5) ^^ 5);
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alias Int = Number!int;
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writeln(Int(3) ^^ 3);
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writeln(Int(0) ^^ -2); // Division by zero.
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}
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