string b="abcde"; string name ="选手"+b[1];

The code you provided is incomplete and the second line is unrelated to the first line. However, assuming you want to access the second character in the string b, the correct code would be:

string b = "abcde";
string name = "选手";
char secondChar = b[1]; // secondChar will be 'b'

Note that string indexing starts from 0, so b[1] corresponds to the second character in the string (which is 'b' in this case). Also, I included a third line to store the second character in a separate variable called secondChar.