foo.cc: In function 'int find(int, int, double)':
foo.cc:15:6: error: 'a' was not declared in this scope
  if (a[mid]>key){
      ^
foo.cc: In function 'int find2(int, int, double)':
foo.cc:26:6: error: 'a' was not declared in this scope
  if (a[mid]<key){
      ^
foo.cc: In function 'int main()':
foo.cc:52:12: error: 'a' was not declared in this scope
   double y=a[i];
            ^
foo.cc: In function 'int find(int, int, double)':
foo.cc:20:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.cc: In function 'int find2(int, int, double)':
foo.cc:32:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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