foo.cc: In function 'int main()':
foo.cc:6:9: error: 'sum' was not declared in this scope
    6 |         sum>>c>>z;
      |         ^~~
foo.cc:7:18: error: expected ';' before 'cout'
    7 |         (x>>c>>z)
      |                  ^
      |                  ;
    8 |         cout<<endl;
      |         ~~~~      
foo.cc:7:14: warning: statement has no effect [-Wunused-value]
    7 |         (x>>c>>z)
      |         ~~~~~^~~~

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