foo.cc: In function 'int main()':
foo.cc:10:6: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  if(n=1) cout << b;
     ~^~
foo.cc:11:11: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  else if(n=2) cout << b << ' ' << b;
          ~^~

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