foo.cc: In function 'int main()':
foo.cc:17:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   17 |  gets(source);
      |             ^
In file included from /usr/include/stdio.h:867,
                 from /usr/include/c++/9/cstdio:42,
                 from foo.cc:3:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:17:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   17 |  gets(source);
      |             ^
In file included from /usr/include/stdio.h:867,
                 from /usr/include/c++/9/cstdio:42,
                 from foo.cc:3:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:18:18: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   18 |  gets(destination);//输入
      |                  ^
In file included from /usr/include/stdio.h:867,
                 from /usr/include/c++/9/cstdio:42,
                 from foo.cc:3:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:18:18: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   18 |  gets(destination);//输入
      |                  ^
In file included from /usr/include/stdio.h:867,
                 from /usr/include/c++/9/cstdio:42,
                 from foo.cc:3:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:27:10: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   27 |  for(; q = strstr(p, source); ) {//循环，strstr是在一个字符串里面给定一个字符串，寻找有没有这个字符串，若有，返回首次出现的指针否则返回NULL（空指针）
      |        ~~^~~~~~~~~~~~~~~~~~~
foo.cc:17:6: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  gets(source);
      |  ~~~~^~~~~~~~
foo.cc:18:6: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
   18 |  gets(destination);//输入
      |  ~~~~^~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccwuA7sL.o: in function `main':
foo.cc:(.text.startup+0x60): warning: the `gets' function is dangerous and should not be used.

Found 10 testcases.
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