a1: text 0.5 -1 87 a2: text 0.25 -2 6 a3: text 0.75 -2 78 a4: text 0.125 -3 89 a5: text 0.375 -3 7 a6: text 0.625 -3 31 a7: text 0.875 -3 0 a8: text 0.0625 -4 43 succ8: line <- 0.1125 -3.2 0.075 -3.8 click succ6: line <- 0.725 -2.2 0.65 -2.8 succ7: line <- 0.775 -2.2 0.85 -2.8 click succ4: line <- 0.225 -2.2 0.15 -2.8 succ5: line <- 0.275 -2.2 0.35 -2.8 a4: text 0.125 -3 6 a2: text 0.25 -2 89 a8: text 0.0625 -4 6 a4: text 0.125 -3 43 click succ2: line <- 0.45 -1.2 0.3 -1.8 succ3: line <- 0.55 -1.2 0.7 -1.8 a2: text 0.25 -2 87 a1: text 0.5 -1 89 click erase succ8 a1: text 0.5 -1 6 a8: text 0.0625 -4 89 a2: text 0.25 -2 6 a1: text 0.5 -1 87 a4: text 0.125 -3 6 a2: text 0.25 -2 43 click succ7: line <- 0.225 -3.8 0.7125 -3.2 a1: text 0.5 -1 0 a7: text 0.875 -3 87 a3: text 0.75 -2 0 a1: text 0.5 -1 78 a6: text 0.625 -3 0 a3: text 0.75 -2 31 click succ6: line <- 0.825 -3 0.675 -3 a1: text 0.5 -1 0 a6: text 0.625 -3 78 a2: text 0.25 -2 0 a1: text 0.5 -1 43 a5: text 0.375 -3 0 a2: text 0.25 -2 7 click succ5: line <- 0.575 -3 0.425 -3 a1: text 0.5 -1 0 a5: text 0.375 -3 43 a3: text 0.75 -2 0 a1: text 0.5 -1 31 click succ4: line <- 0.325 -3 0.175 -3 a1: text 0.5 -1 6 a4: text 0.125 -3 31 a2: text 0.25 -2 6 a1: text 0.5 -1 7 click succ3: line <- 0.25 -2.8 0.625 -2.2 a1: text 0.5 -1 0 a3: text 0.75 -2 7 a2: text 0.25 -2 0 a1: text 0.5 -1 6 click succ2: line <- 0.65 -2 0.35 -2 a1: text 0.5 -1 0 a2: text 0.25 -2 6 click succ1: line <- 0.3 -1.8 0.45 -1.2 click