Fire Emblem - Position Swap

cursorX = 0x0202BBCC
cursorY = 0x0202BBCE

X = 0x0202BD60
Y = 0x0202BD61

c = {}

units = {}
size = 1

while true do
    c = input.get()
    if c.Q then
        units = {}
        size = 1
        for i = 0, 131, 1 do
            if(memory.readbyte(cursorX) == memory.readbyte(X+(i*72)) and memory.readbyte(cursorY) == memory.readbyte(Y+(i*72))) then
                units[size] = i
                size = size + 1
            end
        end
    elseif c.W and size > 0 then
        for i = 1, size-1, 1 do
            memory.writebyte(X+(units[i]*72),memory.readbyte(cursorX))
            memory.writebyte(Y+(units[i]*72),memory.readbyte(cursorY))
        end
    end
    emu.frameadvance()
end