foo.cc: In function 'int main()':
foo.cc:7:11: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
    7 |     gets(s);    //输入
      |           ^
In file included from /usr/include/stdio.h:867,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:7:11: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
    7 |     gets(s);    //输入
      |           ^
In file included from /usr/include/stdio.h:867,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.cc:7:9: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
    7 |     gets(s);    //输入
      |     ~~~~^~~
/usr/bin/ld: /tmp/cc6tlDGG.o: in function `main':
foo.cc:(.text.startup+0x25): warning: the `gets' function is dangerous and should not be used.

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