importCocoa

varstr ="Hello,playground"

structpoint{

varx =0;

vary =init(x:Int,y:Int){

self.x= x;

y= y;

println("init");

}

funcgetCenter()->Int{

return(x+y)/2;

}

mutatingfuncaddOffset(deltaX:Int){//mutating结构体成员变量改变写此特性

x+=deltaX;

y+=deltaY;

}

}

//var v1 = point(x:2,y:3);//没有构造函数时，可以这样调用

//println("\(v1.x),\(v1.y)");

//var v2 = point();//没有构造函数时，可以这样调用

//println("\(v2.x),\(v2.y)");

varv3 =point(x:4,y:5);

"\(v3.x),\y)");

varv4 =v3.getCenter();

addOffset(2,deltaY:2);