/in/foo.cc: In function 'int main()':
/in/foo.cc:73:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
                 if(!flag)
                   ^
/in/foo.cc:89:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
                 if(!flag)
                   ^
/in/foo.cc:105:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
                 if(!flag)
                   ^