foo.cc: In function 'int main()':
foo.cc:23:27: warning: comparison of integer expressions of different signedness: 'int' and 'long unsigned int' [-Wsign-compare]
   23 |         for (int x = 0; x < sizeof(a); x++)
      |                         ~~^~~~~~~~~~~
foo.cc:33:5: error: '_int64' was not declared in this scope
   33 |     _int64 z = 0;
      |     ^~~~~~
foo.cc:36:24: error: 'z' was not declared in this scope
   36 |             if (m[i] > z)
      |                        ^
foo.cc:45:25: error: 'z' was not declared in this scope
   45 |             if (m[i] >= z)
      |                         ^

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