foo.cc: In function ‘bool leap(int)’:
foo.cc:6:18: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
    6 |         if(y%4==0&&y%100!=0||y%400==0)
      |            ~~~~~~^~~~~~~~~~
foo.cc: In function ‘int date(int, int, int, int, int, int)’:
foo.cc:36:20: warning: ‘ret’ may be used uninitialized [-Wmaybe-uninitialized]
   36 |                 ret+=365+leap(i);
      |                 ~~~^~~~~~~~~~~~~
foo.cc:32:13: note: ‘ret’ was declared here
   32 |         int ret,days1,days2;
      |             ^~~