foo.c: In function 'main':
foo.c:6:4: error: variable-sized object may not be initialized
    6 |    char arr1[n]={}
      |    ^~~~
foo.c:7:1: error: expected ',' or ';' before '}' token
    7 | }
      | ^
foo.c:7:1: error: expected declaration or statement at end of input
foo.c:6:9: warning: unused variable 'arr1' [-Wunused-variable]
    6 |    char arr1[n]={}
      |         ^~~~

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