foo.c: In function 'Concat':
foo.c:33:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   33 |         if(x=1)
      |            ^
foo.c:6:15: warning: unused variable 'j' [-Wunused-variable]
    6 |         int i,j,n1,n2;
      |               ^
foo.c: In function 'main':
foo.c:46:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   46 |         gets(s1);
      |         ^~~~
In file included from foo.c:1:
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.c:47:9: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   47 |         gets(s2);
      |         ^~~~
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.c: In function 'Concat':
foo.c:6:20: warning: 'n2' may be used uninitialized [-Wmaybe-uninitialized]
    6 |         int i,j,n1,n2;
      |                    ^~
foo.c:6:17: warning: 'n1' may be used uninitialized [-Wmaybe-uninitialized]
    6 |         int i,j,n1,n2;
      |                 ^~
/nix/store/3r87a2wq1w4l66wnsm7rqvy608mx23h6-binutils-2.40/bin/ld: /tmp/cc21Ruei.o: in function `main':
foo.c:(.text.startup+0x1e): warning: the `gets' function is dangerous and should not be used.

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