foo.c: In function 'main':
foo.c:8:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    8 |  gets(s);
      |  ^~~~
In file included from /usr/include/stdio.h:867,
                 from foo.c:3:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.c:23:14: warning: statement with no effect [-Wunused-value]
   23 |          flag==1;
      |          ~~~~^~~
foo.c:27:11: warning: statement with no effect [-Wunused-value]
   27 |       flag==0;
      |       ~~~~^~~
foo.c:36:14: warning: statement with no effect [-Wunused-value]
   36 |          flag==1;
      |          ~~~~^~~
foo.c:40:10: warning: statement with no effect [-Wunused-value]
   40 |      flag==0;
      |      ~~~~^~~
foo.c:8:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    8 |  gets(s);
      |  ^~~~~~~
/usr/bin/ld: /tmp/ccoH57bZ.o: in function `main':
foo.c:(.text.startup+0x25): warning: the `gets' function is dangerous and should not be used.

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