foo.cc: In function 'int main()':
foo.cc:7:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(a%3==0);
  ^~
foo.cc:8:2: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  {
  ^
foo.cc:11:2: error: 'else' without a previous 'if'
  else
  ^~~~

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