foo.cc: In function 'int cmd(int, int)':
foo.cc:9:9: error: lvalue required as left operand of assignment
    9 |  if(c%d=0)
      |         ^
foo.cc:14:20: error: expected ')' before ';' token
   14 |   return(cmd(d,c%d);
      |         ~          ^
      |                    )
foo.cc:8:3: warning: control reaches end of non-void function [-Wreturn-type]
    8 |  d=min(a,b);
      |  ~^~~~~~~~~

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