/in/foo.cc: In function 'int main()':
/in/foo.cc:29:29: warning: iteration 24 invokes undefined behavior [-Waggressive-loop-optimizations]
  for(int i=1;i<=25;i++) k[i]=i;
                         ~~~~^~
/in/foo.cc:29:15: note: within this loop
  for(int i=1;i<=25;i++) k[i]=i;
              ~^~~~