foo.cc: In function 'int main()':
foo.cc:6:8: warning: unused variable 'm' [-Wunused-variable]
  int n,m,sum;
        ^
foo.cc:7:16: warning: 'n' is used uninitialized in this function [-Wuninitialized]
  for(int i=1; i<=n;i++)
               ~^~~
foo.cc:11:6: warning: 'sum' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<sum;
  ~~~~^~~~~

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