mirror of https://github.com/dirtbags/fluffy.git
27 lines
345 B
C
27 lines
345 B
C
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#include <stdio.h>
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#include <math.h>
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int
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main(int argc, char *argv[])
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{
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size_t len = 0;
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size_t hist[256] = {0};
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int c;
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while ((c = getchar()) != EOF) {
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hist[c] += 1;
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len += 1;
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}
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float H = 0;
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for (int i = 0; i < 256; i += 1) {
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if (hist[i]) {
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float Hi = (float)hist[i]/len;
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H -= Hi * log2(Hi);
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}
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}
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printf("%f\n", H);
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}
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