foo.cc: In function 'int main()':
foo.cc:9:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    9 |         cin >> c1+1 >> c2+1;
      |                ~~^~
foo.cc:9:26: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    9 |         cin >> c1+1 >> c2+1;
      |                        ~~^~

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