47 lines
885 B
C
47 lines
885 B
C
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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struct xorshift32_state {
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uint32_t a;
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};
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uint32_t xorshift32(struct xorshift32_state *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->a;
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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->a = x;
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}
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float rand_xorshift32(struct xorshift32_state *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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struct xorshift32_state** states = malloc(sizeof(struct xorshift32_state*) * 4);
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for(int i=0; i<4;i++){
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states[i] = malloc(sizeof(struct xorshift32_state));
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states[i]->a = (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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