/in/foo.cc: In function 'int main()':
/in/foo.cc:21:24: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if((a1>=11)||(b1>=11)&&abs(a1-b1)>1){
                ~~~~~~~~^~~~~~~~~~~~~~
/in/foo.cc:33:24: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if((a1>=21)||(b1>=21)&&abs(a1-b1)>1){
                ~~~~~~~~^~~~~~~~~~~~~~