foo.c:2:2: error: invalid preprocessing directive #includ; did you mean #include?
    2 | #includ<string.h>
      |  ^~~~~~
      |  include
foo.c: In function 'Init':
foo.c:5:17: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
    5 |         int n = strlen(s);
      |                 ^~~~~~
foo.c:2:1: note: include '<string.h>' or provide a declaration of 'strlen'
    1 | #include<stdio.h>
  +++ |+#include <string.h>
    2 | #includ<string.h>
foo.c:5:17: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
    5 |         int n = strlen(s);
      |                 ^~~~~~
foo.c:5:17: note: include '<string.h>' or provide a declaration of 'strlen'
foo.c: In function 'Add':
foo.c:42:15: error: 'i' undeclared (first use in this function)
   42 |         for(; i<n1; i++)
      |               ^
foo.c:42:15: note: each undeclared identifier is reported only once for each function it appears in
foo.c:56:1: warning: control reaches end of non-void function [-Wreturn-type]
   56 | }
      | ^

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