foo.cc: In function 'int main()':
foo.cc:8:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<=sizeof(a);i++)
                 ~^~~~~~~~~
foo.cc:8:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for(int i=0;i<=sizeof(a);i++)
     ^~~
foo.cc:11:2: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  cout<<b;
  ^~~~

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