判断一个字符串是否为回文

#include <iostream>#include <string>using namespace std;int main(){string str;while(cin>>str){    bool result=true;string::size_type len=str.size();for(string::size_type idx=0;idx!=len/2;idx++){if (str[idx]!=str[len-1-idx]) { result=false;      break;}}if (result)cout<<"yes"<<endl;else  cout<<"no"<<endl; }}