foo.cc: In function 'int main()':
foo.cc:65:9: warning: unused variable 'num' [-Wunused-variable]
   65 |     int num = 0;
      |         ^~~
foo.cc: At global scope:
foo.cc:85:12: warning: left operand of comma operator has no effect [-Wunused-value]
   85 | int mod = (998244353 , 1e9 + 7 ); const double eps = 1e-8;
      |            ^~~~~~~~~
foo.cc:108:15: warning: left operand of comma operator has no effect [-Wunused-value]
  108 | test_cases = (-1 ,0 ,1 ) /* -1: not sure, 0: multi tests, 1: one test */                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        , 0); const long long
      |               ^~
foo.cc:108:22: warning: right operand of comma operator has no effect [-Wunused-value]
  108 | test_cases = (-1 ,0 ,1 ) /* -1: not sure, 0: multi tests, 1: one test */                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        , 0); const long long
      |                      ^

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