/in/foo.cc: In function 'int main()':
/in/foo.cc:7:8: warning: statement has no effect [-Wunused-value]
  for (s;s<=e;s++)
        ^
/in/foo.cc:9:13: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if (s%4==0&& s%100!=0|| s%400==0)
       ~~~~~~^~~~~~~~~~~
/in/foo.cc:14:11: warning: 'cnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<cnt;
           ^