!enemy[x] ? enemy[x]=find(y) :j(y,enemy[x]) ; 
!enemy[y] ? enemy[y]=find(x) : j(x,enemy[y]) ;

上述enemy[]为数组，find（）为void函数 j（ ，）为void函数；

BUT

[Error]third operand to the conditional operator is of type 'void', but the second operand is neither a throw-expression nor of type 'void'