Hoge[] h = new Hoge[]{a,b,c};
var h = new Hoge[]{a,b,c};
var h = new []{a,b,c};

Hage h = new Hage(){A=a,B=b,C=c};
var h = new Hage(){A=a,B=b,C=c};
var h = new Hage{A=a,B=b,C=c}; ←この()が要らないのはなぜですか?