# include<cstdio> # include<iostream> using namespace std; int main(void) { char letter[101]; char ch; cin>>ch; int i = 0; int j = 1; while ( ch!='.' ) {//输入字符串的一个很好的方法,需要学习 letter[++i] = ch; cin>>ch; } //i在上面的while循环中已经被带到了最后 while ( (j<i)&&(letter[i]==letter[j]) ) { --i; j++; } if ( j >= i )//左边和右边的匹配已经判断结束了 cout<<"Yes"<<endl; else cout<<"No"<<endl; return 0; }