/in/foo.cc: In function 'int main()':
/in/foo.cc:7:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if(y%4==0&&y%100!=0||y%400==0)
     ~~~~~~^~~~~~~~~~
/in/foo.cc:10:4: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
    else
    ^~~~
/in/foo.cc:12:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
     return 0; 
     ^~~~~~