foo.c: In function 'Length':
foo.c:4:17: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
    4 |         int l = strlen(a);
      |                 ^~~~~~
foo.c:2:1: note: include '<string.h>' or provide a declaration of 'strlen'
    1 | #include<stdio.h>
  +++ |+#include <string.h>
    2 | int Length(char a[])
foo.c:4:17: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
    4 |         int l = strlen(a);
      |                 ^~~~~~
foo.c:4:17: note: include '<string.h>' or provide a declaration of 'strlen'

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