foo.cc: In function 'void O()':
foo.cc:81:82: warning: suggest parentheses around comparison in operand of '==' [-Wparentheses]
  if ((ishigh==false&&islow==false)||((nowlow==nowhigh)&&((ifhigh!=iflow)||(ifhigh==iflow==false)))) {cout<<"No Answer!";return;}
                                                                            ~~~~~~^~~~~~~
foo.cc:82:32: warning: suggest parentheses around comparison in operand of '==' [-Wparentheses]
  if ((nowlow==nowhigh)&&(ifhigh==iflow==true)) cout<<key<<dengyu<<nowhigh;
                          ~~~~~~^~~~~~~
foo.cc: In function 'void PAS()':
foo.cc:43:32: warning: 'nums' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if (regex_match(data,r1)) nums++;
                            ~~~~^~

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