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  1. #include <limits.h>
  2. #include <math.h>
  3. #include <stdio.h>
  4.  
  5. int main(void) {
  6.     const auto n = 13UL;
  7.     const auto Index = n > 0UL ? (unsigned long)log2(n) : ULONG_MAX;
  8.  
  9.     printf("MSB is: %u\n", Index); // Prints 3 (zero offset)
  10. }
  11.  
Success #stdin #stdout 0s 4532KB
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Standard input is empty
stdout
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MSB is: 3
https://ideone.com/u26vsi
language:
C (gcc 8.3)
created:
6 years ago
visibility:
public

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