/in/foo.cc: In function 'int main()':
/in/foo.cc:9:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  cin >> c1+1 >> c2+1;
         ~~^~
/in/foo.cc:9:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  cin >> c1+1 >> c2+1;
                 ~~^~