foo.cc: In function 'int main()':
foo.cc:15:8: warning: 'sum' may be used uninitialized in this function [-Wmaybe-uninitialized]
    sum += i;
    ~~~~^~~~
foo.cc:16:8: warning: 'cnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
    cnt += 1;
    ~~~~^~~~
foo.cc:14:7: warning: 'j' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if(j%k==i){
      ~^~

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