Text Diff

输入描述:

The first line contains two integers m (1  m  1000) and n (1  n  1000) – the number of lines in the original text and in the modified text separately. The following m lines are the original text and the next n lines compose the modified text. The length of each text line is in the range [0, 100]. Note that m may not be equal to n.

输出描述:

The result of the comparison is based on original text. If one line is not modified, just output the line with one leading space ‘ ‘.  If this line is modified, output two lines: the original line leading with a ‘-‘ and the modified line leading with a ‘+’.

3 4
a
bb
ccc
aa
bb
ccc
dddd

-a
+aa
 bb
 ccc
+dddd

3 3
a
b
c
xx
yy
c

-a
-b
+xx
+yy
 c

备注:

Note that you should use the original text (2~m+1 lines) as base. Also, output the deleted lines first before added ones. E.g. for input [“a”, ”b”, “c”] and [“a”, “c”, “b”], the output should be [“ a”, “-b”, “ c”, “+b”] instead of [“ a”, “+c”, “ b”, “-c”].