36 lines
648 B
C
36 lines
648 B
C
#include <stdio.h>
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#include <stdint.h>
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#include "rand.h"
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static uint64_t sqrt64(uint64_t n) {
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uint64_t g = UINT64_C(1) << 31;
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for (uint64_t c = g; c; g |= c) {
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if (g * g > n) {
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g ^= c;
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}
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c >>= 1;
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}
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return g;
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}
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static uint64_t get_split(uint64_t len) {
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uint64_t rnd;
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rand_fill(&rnd, sizeof(rnd));
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rnd %= (len * len);
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return sqrt64(rnd) + 1;
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}
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int main(int __attribute__ ((unused)) argc, char __attribute__ ((unused)) *argv[]) {
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rand_init();
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for (uint64_t len = 1397; len;) {
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uint64_t consume = get_split(len);
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fprintf(stderr, "consume %ju bytes\n", (uintmax_t) consume);
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len -= consume;
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}
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rand_cleanup();
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}
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