foo.cc: In function 'bool rn(int)':
foo.cc:4:23: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    4 |         return n%4==0 && n%100 || n%400==0;
      |                ~~~~~~~^~~~~~~~
foo.cc: In function 'int main()':
foo.cc:11:42: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   11 |         while(n1+1<n2 || n1<n2 && y1<=y2 && r1<=r2){
      |                          ~~~~~~~~~~~~~~~~^~~~~~~~~
foo.cc:12:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   12 |                 if(y1<=2 && rn(n1) || y1>2 && rn(n1+1)){
      |                    ~~~~~~^~~~~~~~~

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