foo.cc: In function 'int main()':
foo.cc:45:40: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   45 |                 if (y%400==0 || y%4==0 && y%100!=0)
      |                                 ~~~~~~~^~~~~~~~~~~
foo.cc:48:15: warning: 's' may be used uninitialized [-Wmaybe-uninitialized]
   48 |         cout<<s;
      |               ^
foo.cc:4:19: note: 's' was declared here
    4 |         int y,m,d,s;
      |                   ^

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