42 lines
879 B
C
42 lines
879 B
C
#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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uint32_t xorshift32(uint32_t* state)
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{
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/* Algorithm "xor" from p. 4 of Marsaglia, "Xorshift RNGs" */
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uint32_t x = *state;
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x ^= x << 13;
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x ^= x >> 17;
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x ^= x << 5;
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return *state = x;
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}
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float rand_xorshift32(uint32_t* state){
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return (float) xorshift32(state) / (float) UINT32_MAX;
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}
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int main(){
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uint32_t** states = malloc(4 * sizeof(uint32_t*));
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for(int i=0; i<4;i++){
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states[i] = malloc(sizeof(uint32_t));
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*states[i] = (uint32_t) i + 1;
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}
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for(int i=0; i<1000000000;i++){
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uint32_t x = xorshift32(states[0]);
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float y = rand_xorshift32(states[1]);
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// printf("%u\n", x);
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// printf("%f\n", y);
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}
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for(int i=0; i<4;i++){
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free(states[i]);
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}
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free(states);
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return 0;
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}
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// See <https://stackoverflow.com/questions/53886131/how-does-xorshift32-works>
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// https://en.wikipedia.org/wiki/Xorshift
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