Saturday puzzles: city construction - spiral
Puzzle 1
1207 City construction RS 07-11-15
Place all buildings in the grid. Buildings may be rotated. They may not touch each other, not even diagonally. Draw a closed loop that passes through all the remaining white cells. The loop does not cross or overlap itself. The given grid is a spiral. Building segments are numbered from 1 to 30, starting from the entrance of the spiral (top left) and moving towards the center. The numbers outside the grid represent the sum of the building segments in the corresponding row or column.