foo.cc: In function 'int ys(int*, int)':
foo.cc:18:9: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   18 |  return m;
      |         ^
foo.cc: In function 'int main()':
foo.cc:27:14: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |  cout<<ys(a,n)<<endl;
      |              ^

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