Maestro n° 100 : Page 84 - Gr 81
L1C1 -5- L1C3 =5= L9C3 -5-1- L9C3 =1= L9C2 -1-9- L9C2 =9= L2C2 -9-8- L2C2 =8= L1C1 donc L1C1 ≠ 5