29 lines
600 B
Zig
29 lines
600 B
Zig
//! Linear congruential generator
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//!
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//! X(n+1) = (a * Xn + c) mod m
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//!
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//! PRNG
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const std = @import("std");
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/// Linear congruent generator where the modulo is `std.math.maxInt(T)`,
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/// wrapping over the integer.
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pub fn Wrapping(comptime T: type) type {
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return struct {
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xi: T,
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a: T,
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c: T,
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pub fn init(xi: T, a: T, c: T) LcgSelf {
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return .{ .xi = xi, .a = a, .c = c };
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}
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pub fn next(lcg: *LcgSelf) T {
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lcg.xi = (lcg.a *% lcg.xi) +% lcg.c;
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return lcg.xi;
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}
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const LcgSelf = @This();
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};
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}
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