foo.c: In function 'main':
foo.c:13:19: warning: no closing ']' for '%[' format [-Wformat=]
   13 |         scanf("%[]s",m);
      |                   ^
foo.c:14:19: warning: no closing ']' for '%[' format [-Wformat=]
   14 |         scanf("%[]s",n);
      |                   ^
foo.c: In function 'Length':
foo.c:8:1: warning: control reaches end of non-void function [-Wreturn-type]
    8 | }
      | ^

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