38 lines
786 B
Common Lisp
38 lines
786 B
Common Lisp
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//! Pseudo-random number generation using a LFSR algorithm
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static state: u64 = 0xdeadbeefdeadbeef;
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pub fn seed(seed: u64) {
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state = seed;
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}
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pub fn lfsr_next() {
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state ^= state >> 7;
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state ^= state << 9;
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state ^= state >> 13;
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}
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/// Returns a pseudorandom byte
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pub fn rand() -> u8 {
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for _ in 0..8 {
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lfsr_next()
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}
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state & 0xff
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}
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// Prints a maze out of diagonal box drawing characters, ['╲', '╱']
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fn mazel(width: u64, height: u64) {
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let walls = ['\u{2571}', '\u{2572}'];
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rand_rect(width, height, walls)
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}
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// Prints a rectangle with the provided walls
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fn rand_rect(width: u64, height: u64, walls: [char; 2]) {
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for _ in 0..height {
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for _ in 0..width {
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print(walls[rand() % 2])
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}
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println()
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}
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}
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