foo.cc: In function 'int main()':
foo.cc:23:15: error: expected ';' before '<=' token
  for(int i=a,i<=b;i++)
               ^~
foo.cc:23:15: error: expected primary-expression before '<=' token
foo.cc:30:2: error: 'cou' was not declared in this scope
  cou<<ans<<endl;
  ^~~
foo.cc:30:2: note: suggested alternative: 'cos'
  cou<<ans<<endl;
  ^~~
  cos

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