foo.cc: In function 'int main()':
foo.cc:40:16: error: 'ans' was not declared in this scope; did you mean 'abs'?
   40 |    printf("%d",ans);
      |                ^~~
      |                abs
foo.cc:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:34:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   34 |   scanf("%d",&a[i]);
      |   ~~~~~^~~~~~~~~~~~

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