foo.cc: In function 'int main()':
foo.cc:9:22: warning: 'n' is used uninitialized [-Wuninitialized]
    9 |         for(int i=0;i<n;i++)
      |                     ~^~
foo.cc:7:9: note: 'n' was declared here
    7 |     int n;
      |         ^

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