foo.cc: In function 'int main()':
foo.cc:13:16: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   13 |   if(a==11&&a>b&&a-b>=2||b==11&&b>a&&b-a>=2){
      |      ~~~~~~~~~~^~~~~~~~
foo.cc:17:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   17 |   else if(a>=11&&a>b&&a-b>=2||b>=11&&b>a&&b-a>=2){
      |           ~~~~~~~~~~^~~~~~~~
foo.cc:27:16: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   27 |   if(a==21&&a>b&&a-b>=2||b==21&&b>a&&b-a>2){
      |      ~~~~~~~~~~^~~~~~~~
foo.cc:32:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   32 |   else if(a>=21&&a>b&&a-b>=2||b>=21&&b>a&&b-a>=2){
      |           ~~~~~~~~~~^~~~~~~~

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