foo.cc: In function 'void bubble(int*, int)':
foo.cc:8:3: error: 'swap' was not declared in this scope
   swap (array[j-1],array[j]);
   ^~~~
foo.cc: In function 'int main()':
foo.cc:13:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&x);
  ~~~~~^~~~~~~~~
foo.cc:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&a[i]);
   ~~~~~^~~~~~~~~~~~

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