要把下面文件的内容改了，

Program name: granite
Author: Gilbert Bates
Company: RockSoft
Department: R&D
Phone: +1 503 555-0095
Date: Tues March 9, 2004
Version: 2.1
Size: 21k
Status: Final beta

改成这样：

Program name: granite
Author: Judas
Company: RockSoft
Department: R&D
Date: Wed Jul  3 02:52:49 EDT 2019
Version: 2.1
Size: 21k
Status: Final beta

下面的代码中，第102行想实现删除phone的那一行文件内容，但实际上没有删除最后的换行符

     98 chomp(my $date = `date`);
     99 $^I = ".bak";
    100 while(<>){
    101     s/Author:.*/Author: Wei Yan/;
    102     s/^Phone.*//;
    103     s/Date.*/Date: $date/;
    104     print;
    105 }

导致文件内容产生了一行空格：

Program name: granite
Author: Wei Yan
Company: RockSoft
Department: R&D

Date: Wed Jul  3 02:52:49 EDT 2019
Version: 2.1
Size: 21k
Status: Final beta

如果把102行代码改为：

    102     s/^Phone.*//s;

或者

    102     s/^Phone.*\n//s;

就能把phone那一行完全删除