local N = io.read("*n")
local ans = {}
for i=0, 18 do ans[i] = 0 end

function read()
  local c = ' '
  while true do
    c = io.read(1)
    if c > ' ' then break end
  end
  local s = "" .. c
  while true do
    c = io.read(1)
    if c <= ' ' then break end
    s = s .. c
  end
  return s
end

local ans = {}
for i = 1, 20 do ans[i] = 0 end

for i=1,N do 
  s = string.reverse(read())
  for j=1, #s do
    ans[j] = ans[j] + tonumber(string.sub(s, j, j))
  end
end

for i = 1, 19 do
  ans[i + 1] = ans[i + 1] + math.floor(ans[i] / 10)
  ans[i] = ans[i] % 10
end

local i = 20
while i >= 1 and ans[i] == 0 do i = i - 1 end

if i == 0 then
  print(0)
else
  for i = i, 1, -1 do
    io.write(string.format("%01d", ans[i]))
  end
  io.write("\n")
end