foo.cc: In function 'int f1(int, int, double)':
foo.cc:13:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   13 |   mid = l + r >> 1;
      |         ~~^~~
foo.cc: In function 'int f2(int, int, double)':
foo.cc:23:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   23 |   mid = l + r + 1 >> 1;
      |         ~~~~~~^~~
foo.cc: In function 'int main()':
foo.cc:54:7: warning: 'ansy' may be used uninitialized in this function [-Wmaybe-uninitialized]
   54 |    << ansy << endl;
      |       ^~~~
foo.cc:53:10: warning: 'ansx' may be used uninitialized in this function [-Wmaybe-uninitialized]
   53 |  cout << ansx << endl
      |          ^~~~

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