【入门夯实】连续字符：最长连续相同字符的扫描写法

local s = "aabbbcd"
for i = 1, #s do
    if string.sub(s, i, i) == string.sub(s, i + 1, i + 1) then
        -- i = #s 时右侧越界返回空串
    end
end

local s = "aabbbcd"
local best, cur = 1, 1
for i = 1, #s - 1 do
    if string.byte(s, i) == string.byte(s, i + 1) then
        cur = cur + 1
        if cur > best then
            best = cur
        end
    else
        cur = 1
    end
end
print(best)

local s = "aabbbcd"
local best, cur, pos = 1, 1, 1
for i = 2, #s do
    if string.byte(s, i) == string.byte(s, i - 1) then
        cur = cur + 1
    else
        cur = 1
    end
    if cur > best then
        best, pos = cur, i - cur + 1
    end
end
print(best, string.sub(s, pos, pos + best - 1))