/in/foo.cc: In member function 'void DATE::cal()':
/in/foo.cc:22:15: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(y1%4==0&&y1%100!=0||y1%400==0)
        ~~~~~~~^~~~~~~~~~~
/in/foo.cc:43:15: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(y2%4==0&&y2%100!=0||y2%400==0)
        ~~~~~~~^~~~~~~~~~~
/in/foo.cc:57:13: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(i%4==0&&i%100!=0||i%400==0)
       ~~~~~~^~~~~~~~~~