foo.cc: In function 'int main()':
foo.cc:16:3: error: expected '}' before 'else'
   16 |   else
      |   ^~~~
foo.cc:13:28: note: to match this '{'
   13 |   if (i*i*i+j*j*j+k*k*k==n){
      |                            ^
foo.cc: At global scope:
foo.cc:20:5: error: expected unqualified-id before 'return'
   20 |     return 0;
      |     ^~~~~~
foo.cc:21:1: error: expected declaration before '}' token
   21 | }
      | ^

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