foo.cc: In function 'int main()':
foo.cc:27:9: error: 'st' was not declared in this scope
    cin>>st[i];
         ^~
foo.cc:27:9: note: suggested alternative: 'str'
    cin>>st[i];
         ^~
         str
foo.cc:31:12: error: 'st' was not declared in this scope
    cout>>f(st[i]);
            ^~
foo.cc:31:12: note: suggested alternative: 'str'
    cout>>f(st[i]);
            ^~
            str
foo.cc:24:11: warning: unused variable 'str' [-Wunused-variable]
   string *str = new string[n];
           ^~~

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