/in/foo.c: In function 'main':
/in/foo.c:8:7: warning: iteration 97 invokes undefined behavior [-Waggressive-loop-optimizations]
   f[i]=f[i-1]+f[i-2];
   ~~~~^~~~~~~~~~~~~~
/in/foo.c:7:2: note: within this loop
  for(i=3;i<=100;i++)
  ^~~