local q = io.read("*n")
local function solve(a, b, c)
  local cnt = 0
  if a == c then
    if a == 1 then return -1
    else
      a = a - 1
      cnt = cnt + 1
    end
  elseif c < a then
    a, c = c, a
  end
  if b < a then
    return cnt
  elseif a == b then
    if b == 1 then return -1
    else return cnt + 1
    end
  elseif b <= c then
    if 2 <= b - a then
      local cand = c - b + 1
      if 1 < a then cand = math.min(cand, b - a + 1) end
      return cnt + cand
    else
      if a == 1 then return -1
      else
        return cnt + b - a + 1
      end
    end
  else
    return cnt
  end
  return cnt
end
for i = 1, q do
  local a, b, c = io.read("*n", "*n", "*n")
  print(solve(a, b, c))
end