foo.cc: In function 'int main()':
foo.cc:9:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    9 |                 if(a1%100!=0&&a1%4==0||a1%400==0){
      |                    ~~~~~~~~~^~~~~~~~~
foo.cc:19:45: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   19 |                                 if(b1%100!=0&&b1%4==0||b1%400==0){
      |                                    ~~~~~~~~~^~~~~~~~~
foo.cc:31:45: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   31 |                                 if(b1%100!=0&&b1%4==0||b1%400==0){
      |                                    ~~~~~~~~~^~~~~~~~~

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