Enum advent_solutions::advent2017::day18::Instruction [−] [src]

pub enum Instruction {
    Snd(Value),
    Set(char, Value),
    Add(char, Value),
    Mul(char, Value),
    Mod(char, Value),
    Rcv(char),
    Jgz(Value, Value),
}

There aren't that many instructions, so it shouldn't be hard to figure out what they do. Here's what you determine:

snd X plays a sound with a frequency equal to the value of X.
set X Y sets register X to the value of Y.
add X Y increases register X by the value of Y.
mul X Y sets register X to the result of multiplying the value contained in register X by the value of Y.
mod X Y sets register X to the remainder of dividing the value contained in register X by the value of Y (that is, it sets X to the result of X modulo Y).
rcv X recovers the frequency of the last sound played, but only when the value of X is not zero. (If it is zero, the command does nothing.)
jgz X Y jumps with an offset of the value of Y, but only if the value of X is greater than zero. (An offset of 2 skips the next instruction, an offset of -1 jumps to the previous instruction, and so on.)