foo.cc: In function ‘int main()’:
foo.cc:22:14: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
   22 |     if(y%4==0&&y%100!=0||y%400==0)
      |        ~~~~~~^~~~~~~~~~
foo.cc:5:15: warning: unused variable ‘i’ [-Wunused-variable]
    5 |     long long i=0,y,m,d,leap=0;
      |               ^