a := 1
a = a + 1
b := a - 2 * 3
b = 2 + b * a
c := -b
//a := 1
//b := 1 - 2 * 2 + 5
//c := a + b * 2 * b
//d := a + 4 * b * a
/*x := 1
y := 1
i := 60
while i {
z := x + y
y = x
x = z
print(z)
i = i - 1
}*/
