foo.c: In function 'main':
foo.c:7:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    7 |     gets(s1);
      |     ^~~~
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.c:8:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    8 |  gets(s2);
      |  ^~~~
In file included from /usr/include/stdio.h:867,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
  235 | gets (char *__str)
      | ^~~~
foo.c:9:11: warning: format '%d' expects argument of type 'int', but argument 2 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
    9 |  printf("%d %d",strlen(s1),strlen(s2));
      |          ~^     ~~~~~~~~~~
      |           |     |
      |           int   size_t {aka long unsigned int}
      |          %ld
foo.c:9:14: warning: format '%d' expects argument of type 'int', but argument 3 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
    9 |  printf("%d %d",strlen(s1),strlen(s2));
      |             ~^             ~~~~~~~~~~
      |              |             |
      |              int           size_t {aka long unsigned int}
      |             %ld
foo.c:5:8: warning: unused variable 'b' [-Wunused-variable]
    5 |  int a,b;
      |        ^
foo.c:5:6: warning: unused variable 'a' [-Wunused-variable]
    5 |  int a,b;
      |      ^
foo.c:7:5: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    7 |     gets(s1);
      |     ^~~~~~~~
foo.c:8:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    8 |  gets(s2);
      |  ^~~~~~~~
/usr/bin/ld: /tmp/ccgDmmJG.o: in function `main':
foo.c:(.text.startup+0x4d): warning: the `gets' function is dangerous and should not be used.

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