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35 lines
762 B
C
35 lines
762 B
C
/* License: MIT Copyright (C) 2007-2018 - pancake@nopcode.org */
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#if 0
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From Wikipedia, the free encyclopedia
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In information theory, the Hamming distance between two strings of equal
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length is the number of positions for which the corresponding symbols
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are different. Put another way, it measures the minimum number of
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substitutions required to change one into the other, or the number of
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errors that transformed one string into the other.
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#endif
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#include "r_types.h"
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static int hamdist(int x, int y) {
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int dist = 0, val = x ^ y;
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while (val) {
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dist++;
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val &= val - 1;
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}
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return dist;
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}
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R_API ut8 r_hash_hamdist(const ut8 *buf, int len) {
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int i, x, y;
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x = y = i = 0;
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for (i = 0; i < len; i++) {
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y = buf[i];
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x = hamdist (x, y);
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}
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return x;
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}
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