foo.cc: In function 'int main()':
foo.cc:7:12: error: expected unqualified-id before '=' token
    7 |         int=0;
      |            ^
foo.cc:10:19: error: 't' was not declared in this scope
   10 |                   t+=i;
      |                   ^
foo.cc:12:15: error: 't' was not declared in this scope
   12 |         cout<<t<<endl;
      |               ^

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