foo.cc: In function 'int max(int*, int)':
foo.cc:24:9: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
   24 |  return index;
      |         ^~~~~
foo.cc: In function 'int main()':
foo.cc:38:19: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
   38 |  cout << max(c, 10) << endl;
      |                   ^

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