#include <stdio.h>
#include <time.h>
 
#define START 22
#define END 45
 
unsigned fibo( unsigned n )
{
  if ( n > 2 )
  {
    return fibo(n-1) + fibo(n-2);
  }
  else
  {
    return 1;
  }
}
 
void main() {
   int i;
   int f;
   time_t t1, t2;
   float s;

   for (i = START; i < END; i++) {
     t1 = clock();
     f = fibo(i);
     t2 = clock();
     printf("fibo(%d)=%d ", i, f);
     s = (float)(t2 - t1) / (float) CLOCKS_PER_SEC;
     printf("in %3.1f seconds\n", s);
   }
}

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