/in/foo.cc: In function 'int leap(int)':
/in/foo.cc:5:15: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  return a%4==0&&a%100!=0||a%400==0;
         ~~~~~~^~~~~~~~~~
/in/foo.cc: In function 'int yearday(int, int, int)':
/in/foo.cc:16:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int i=1;i<y;i++)
  ^~~
/in/foo.cc:18:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   return a+z;
   ^~~~~~
/in/foo.cc:18:12: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return a+z;
            ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:18:12: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return a+z;
            ^
/in/foo.cc:15:6: note: 'a' was declared here
  int a;
      ^