foo.cc: In function 'int main()':
foo.cc:30:19: warning: iteration 9 invokes undefined behavior [-Waggressive-loop-optimizations]
    while(a[i]==a[j])
                ~~~^
foo.cc:27:11: note: within this loop
  for(i=0;i<10;i++)
          ~^~~
foo.cc:40:5: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
    x++;
    ~^~

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