foo.cc: In function 'int main()':
foo.cc:14:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   14 |  gets(a);
      |        ^
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:14:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   14 |  gets(a);
      |        ^
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:14:6: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
   14 |  gets(a);
      |  ~~~~^~~
foo.cc:15:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |  scanf("%d%d", &first, &lenth);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccBYGWDc.o: in function `main':
foo.cc:(.text.startup+0x38): warning: the `gets' function is dangerous and should not be used.

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