foo.cc:36:12: warning: missing terminating " character
   36 |     printf(" x1, x2, x3);
      |            ^
foo.cc:36:12: error: missing terminating " character
   36 |     printf(" x1, x2, x3);
      |            ^~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:37:5: error: expected primary-expression before 'return'
   37 |     return 0;
      |     ^~~~~~
foo.cc:35:12: warning: unused variable 'x1' [-Wunused-variable]
   35 |     double x1 = Newton(-5.0), x2 = Newton(5.0), x3 = Newton(20.0);
      |            ^~
foo.cc:35:31: warning: unused variable 'x2' [-Wunused-variable]
   35 |     double x1 = Newton(-5.0), x2 = Newton(5.0), x3 = Newton(20.0);
      |                               ^~
foo.cc:35:49: warning: unused variable 'x3' [-Wunused-variable]
   35 |     double x1 = Newton(-5.0), x2 = Newton(5.0), x3 = Newton(20.0);
      |                                                 ^~

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