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  1. #include <stdio.h>
  2. #include <stdint.h>
  3.  
  4. uint32_t log2(uint32_t n)
  5. {
  6.     float f = n;
  7.     return (*reinterpret_cast<uint32_t *>(&f) >> 23) - 127;
  8. }
  9.  
  10. int main()
  11. {
  12.     uint32_t n;
  13.     while(scanf("%u", &n) == 1)
  14.     {
  15.         printf("%u\n", log2(n));
  16.     };
  17.     return 0;
  18. }
Success #stdin #stdout 0s 2900KB
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https://ideone.com/rqRqBx
language:
C++ (gcc 8.3)
created:
12 years ago
visibility:
secret

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