foo.c:2:1: warning: return type defaults to 'int' [-Wimplicit-int]
    2 | sczc(char s[],int si,int len)
      | ^~~~
foo.c: In function 'main':
foo.c:15:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   15 |  gets(s);
      |  ^~~~
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: In function 'sczc':
foo.c:10:1: warning: control reaches end of non-void function [-Wreturn-type]
   10 | }
      | ^
foo.c: In function 'main':
foo.c:15:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
   15 |  gets(s);
      |  ^~~~~~~
foo.c:16:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d %d",&si,&len);
      |  ^~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccdAQssA.o: in function `main':
foo.c:(.text.startup+0x46): warning: the `gets' function is dangerous and should not be used.

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