foo.c: In function 'fun':
foo.c:20:17: warning: unknown escape sequence: '\040'
          printf("\%c\ ", i + 'a', k[i]);
                 ^~~~~~~
foo.c:20:17: warning: too many arguments for format [-Wformat-extra-args]
foo.c: In function 'main':
foo.c:25:4: warning: 'gets' is deprecated [-Wdeprecated-declarations]
    gets(s);
    ^~~~
In file included from /usr/include/stdio.h:862:0,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.c:25:4: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
    gets(s);
    ^~~~~~~
foo.c: In function 'fun':
foo.c:5:21: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]
    int k[26] = {0}, n, i, max = 0;
                     ^
/tmp/cczd3z3v.o: In function `main':
foo.c:(.text.startup+0x32): warning: the `gets' function is dangerous and should not be used.

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