foo.cc: In function 'int findMEX(int*, int)':
foo.cc:14:1: warning: control reaches end of non-void function [-Wreturn-type]
   14 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:46:8: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
   46 |  system("pause");
      |  ~~~~~~^~~~~~~~~

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