foo.cc: In function 'int main()':
foo.cc:8:23: warning: 'n' is used uninitialized [-Wuninitialized]
    8 |         vector<int>k(n);
      |                       ^
foo.cc:7:13: note: 'n' declared here
    7 |         int n;
      |             ^
foo.cc:32:24: warning: 'y' may be used uninitialized [-Wmaybe-uninitialized]
   32 |         cout<< x<<" "<<y;
      |                        ^
foo.cc:28:13: note: 'y' was declared here
   28 |         int y;
      |             ^

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