diff結果分析

例一

#text1
i love story
i love book
i like flower
#text2
i love story
i love milk
i don't love book
i love beibei
i like flower
#result
d2 1
a2 3
i love milk
i don't love book
i love beibei
a3 2

例二

text1
i love story   
i love book      #delete
i like flower
i like suger

text2
i love story
i love milk           #delete     #add 
                        #delete
i don't love book      #delete
i love beibei
i like suger

d2 3   #刪除三行
a4 1   #在第四行插入一行
i love milk
a5 3    #在第五行插入三行
i don't love book
i love beibei
i like suger

#text1
i love story
i love book
i like flower
i love beibei
i like suger
i love leaves
#text2 
i love story
i love milk

i don't love book
i love beibei
i like suger
#######################result##########
d2 2    #刪除兩行
a3 3    #增長三行
i love milk

i don't love book
d6 1    #刪除兩行