foo.c: In function 'main':
foo.c:5:9: error: 'n' undeclared (first use in this function)
    5 |         n=0;
      |         ^
foo.c:5:9: note: each undeclared identifier is reported only once for each function it appears in
foo.c:8:15: warning: missing terminating " character
    8 |         scanf("%d,&a);
      |               ^
foo.c:8:15: error: missing terminating " character
    8 |         scanf("%d,&a);
      |               ^~~~~~~~
foo.c:9:9: error: expected expression before 'while'
    9 |         while(i!='\n')
      |         ^~~~~
foo.c:19:18: error: expected ';' before '}' token
   19 |         return 0;
      |                  ^
      |                  ;
   20 | }
      | ~                 
foo.c:7:14: warning: unused variable 'arr' [-Wunused-variable]
    7 |         char arr[10086];
      |              ^~~
foo.c:6:14: warning: unused variable 'i' [-Wunused-variable]
    6 |         char i;
      |              ^
foo.c:4:13: warning: unused variable 'n\U0000ff0ca' [-Wunused-variable]
    4 |         int n，a;
      |             ^~~~

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