foo.cc: In function 'int main()':
foo.cc:23:12: warning: variable 'k' set but not used [-Wunused-but-set-variable]
  int sum=0,k,count=0,flag;
            ^
foo.cc:23:14: warning: unused variable 'count' [-Wunused-variable]
  int sum=0,k,count=0,flag;
              ^~~~~

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