foo.c: In function 'main':
foo.c:8:13: error: 'i' undeclared (first use in this function)
    8 |         for(i=0;i<n;i++)
      |             ^
foo.c:8:13: note: each undeclared identifier is reported only once for each function it appears in
foo.c:13:13: error: 'number' undeclared (first use in this function); did you mean 'Number'?
   13 |         for(number=0;number<Number;number++)
      |             ^~~~~~
      |             Number
foo.c:12:21: warning: variable 'c' set but not used [-Wunused-but-set-variable]
   12 |         int a=0,b=1,c=0;
      |                     ^
foo.c:7:13: warning: variable 'a' set but not used [-Wunused-but-set-variable]
    7 |         int a[n];
      |             ^
foo.c:5:11: warning: unused variable 'temp' [-Wunused-variable]
    5 |     int n,temp;
      |           ^~~~

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