foo.cc: In function 'int main()':
foo.cc:8:14: warning: 'n' is used uninitialized in this function [-Wuninitialized]
    8 |  int a[m+5][n+5];
      |             ~^~
foo.cc:8:9: warning: 'm' is used uninitialized in this function [-Wuninitialized]
    8 |  int a[m+5][n+5];
      |        ~^~

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