foo.c: In function 'main':
foo.c:5:11: error: 'n' undeclared (first use in this function)
    5 |     int a[n]={1,2,3,4,5....999]
      |           ^
foo.c:5:11: note: each undeclared identifier is reported only once for each function it appears in
foo.c:5:23: error: too many decimal points in number
    5 |     int a[n]={1,2,3,4,5....999]
      |                       ^~~~~~~~
foo.c:5:31: error: expected '}' before ']' token
    5 |     int a[n]={1,2,3,4,5....999]
      |              ~                ^
foo.c:5:31: error: expected ',' or ';' before ']' token
foo.c:6:15: error: 'i' undeclared (first use in this function)
    6 |   for(int i=0;i<n-1;i++）
      |               ^
foo.c:6:24: error: stray '\357' in program
    6 |   for(int i=0;i<n-1;i++）
      |                        ^
foo.c:6:25: error: stray '\274' in program
    6 |   for(int i=0;i<n-1;i++）
      |                         ^
foo.c:6:26: error: stray '\211' in program
    6 |   for(int i=0;i<n-1;i++）
      |                          ^
foo.c:6:24: error: expected ';' before '{' token
    6 |   for(int i=0;i<n-1;i++）
      |                        ^
      |                        ;
    7 |    {
      |    ~                    
foo.c:5:9: warning: unused variable 'a' [-Wunused-variable]
    5 |     int a[n]={1,2,3,4,5....999]
      |         ^

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