Google lab proficiency testing (question 1 and answer)

As you can see in MoP:
By the end of October this year, google published a Google lab competency disposition test in several professional magazines, such as the Massachusetts technical comments, linuxjournal, Mensa, and today's physics., start with "Try it! Send the answer back to Google. You hope to visit the Google headquarters and become one of us ".
Original article address:
Http://news.mop.com/6/503/50559.html

So I started my first question.
After spending half an hour, notepad wrote several pages. The answer is 777589-188103 = 589486 (can be exchanged)
Q:

1. Answer the following hidden equations. Values of M and E can be exchanged, but 0 is not allowed for the first one:

Wwwdot-Google = dotcom

Answer:

100,000, and 10
WWW d o t
-G o g L E
------------------
D o T c o m

Hint:

1. A total of 10 different letters appear, only M and ecan be exchanged, So 0 to 9 will appear

2. The column with ten digits should be o-L = O (ten digits, with no bits ==> L = 0)
Or 10 + O-L = O (ten bits ==> L = 10)
Or o-L = O + 1 (with a bid of => L =-1)
Or 10 + O-L = O + 1 (ten digits have bits ==> L = 9)
==> L = 0 (ten digits, no bid for each position)
Or l = 9 (10 digits have a bid)

3. Wanhe qianna Column
W-O = O, W-O = T, and O <> T, it indicates that there must be an advance.

When there is no borrow for bits:
3.1. If W = O + O (tens of thousands of digits) Then W = O + t + 1 (thousands) ==>
W = G + D, W = O + O, O = T +, 10 + D = G + C, L = 0
(Or 10 + D = G + C + 1, L = 9)
==> Even number enumeration for W ==> no solution
3.2. If W = O + 1 (ten thousand bits) Then W = O + T (thousand bits) ==>
W = G + D, W = O + 1, 10 + W = O + T (or 10 + W = O + t + 1)
==> T = 11 or T = 10 ==> no solution

When ten thousand bits have a borrow space:
3.2. If 10 + W = O + O (tens of thousands of digits) Then W = O + T (Thousands of digits) =>
O = 10 + T ==> no solution
3.3. If 10 + W = O + 1 (tens of thousands of digits), then 10 + W = O + T (thousands) =>
W = G + D + 1, W + 10 = O + 1, t = O + 1,
(D = G + C, L = 0) or (D = G + C + 1, L = 9) => enumerate W = 1, 3, 5, 7
==> 777589-188103 = 589486 (interchangeable)