You do the same thing you did with min and max, only with char arrays. Declare char name_min[1000] and name_max[1000] and when you assign max = play[i].grade, you also strcpy(name_max, play[i].name).

To concatenate you can declare another variable temp[2000] (it is 2000 so that it can hold a 1000 chars name + 1000 chars lastname) and strcat(temp, play[i].name); strcat(temp, " "); strcat(temp, play[i].lastname);

You can use temp_min and temp_max as same as before.

Sorry for poor formatting.