_{a = 2}

b = 6

_{c = 4d = 7}

_{a = 2b = 6}

c = c / 2

_{d = 7}

_{a = 2}

b = b - 4

_{c = c / 2d = 7}

_{a = 2b = b - 4}

c = c - 3

_{d = 7}

_{a = 2}

b = b / 2

_{c = c - 3d = 7}

a = a / 2

_{b = b / 2c = c - 3d = 7}

a = a + 4

_{b = b / 2c = c - 3d = 7}

_{a = a + 4}

b = b - 2

_{c = c - 3d = 7}

a = a + 4

_{b = b - 2c = c - 3d = 7}

a = a - 4

_{b = b - 2c = c - 3d = 7}

_{a = a - 4b = b - 2}

c = c + 10

_{d = 7}

_{a = a - 4}

b = b + 3

_{c = c + 10d = 7}

_{a = a - 4b = b + 3c = c + 10}d = d * 2

_{a = a - 4}

b = b + 4

_{c = c + 10d = d * 2}

_{a = a - 4}

b = b + 12

_{c = c + 10d = d * 2}

_{a = a - 4b = b + 12c = c + 10}d = d + 7

_{a = a - 4b = b + 12c = c + 10}d = d + 9

_{a = a - 4b = b + 12c = c + 10}d = d / 6

_{a = a - 4b = b + 12c = c + 10}d = d + 8

_{a = a - 4}

b = b + 11

_{c = c + 10d = d + 8}

_{a = a - 4}

b = b + 12

_{c = c + 10d = d + 8}