foo.cc: In function 'int main()':
foo.cc:16:63: warning: 'x' may be used uninitialized [-Wmaybe-uninitialized]
   16 |                                 if(a[i]==a[j]+a[k]&&j!=i&&k!=j&&x!=i)
      |                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
foo.cc:6:15: note: 'x' was declared here
    6 |         int n,x;
      |               ^

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