foo.c: In function 'main':
foo.c:18:21: warning: comparison of constant '3' with boolean expression is always true [-Wbool-compare]
   18 |         if(0<abs(dx)<3 && abs(dx)+abs(dy)==3)
      |                     ^
foo.c:18:13: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   18 |         if(0<abs(dx)<3 && abs(dx)+abs(dy)==3)
      |            ~^~~~~~~~

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