foo.cc: In function 'int main()':
foo.cc:11:3: error: 'ans' was not declared in this scope; did you mean 'abs'?
   11 |   ans+=x;
      |   ^~~
      |   abs
foo.cc:13:32: error: 'ans' was not declared in this scope; did you mean 'abs'?
   13 |  cout<<fixed<<setprecision(2)<<ans/n;
      |                                ^~~
      |                                abs
foo.cc:6:8: warning: unused variable 'a' [-Wunused-variable]
    6 |  int n,a[105]={0},j=0,x;
      |        ^
foo.cc:6:19: warning: unused variable 'j' [-Wunused-variable]
    6 |  int n,a[105]={0},j=0,x;
      |                   ^

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