In an empty rectangular room in the sizes АхВхС (the length, width, height) has fallen to the floor the fallen asleep fly. The spider who was on one of walls, or on a room’s floor, has started to move to it on the shortest way.
On what distance it thus will move?
Input
In the first line it is set the sizes of a room А, В, С. In the second line - co-ordinates of a fly on the floor X1, Y1, and spider X2, Y2, Z2.
All input date - the integers which are not exceeding 500.
Output
One line – the distance on which the spider will move, calculated to within 2 signs after a decimal point.