缘由https://bbs.csdn.net/topics/396428505
cpp
void 美丽字符串()
{
string zf = ""; int j = 0, b = 0, sl[47]{}, wi = 0;
cin >> zf; zf += "0";// zf.push_back('0');
while (zf[j] != '0')if (zf[b] == zf[j])++sl[b], b = 0, ++j; else ++b;
//if ((wi = zf.find(zf[j++])) != string::npos)++sl[wi];
j = 0;
while (sl[j])if (sl[j++] % 2){ cout << "No"; return; }
cout << "Yes";
}