text: var student = /** @class */ (function () {
      function student(rollno, name, math, phy, che) {
          this.rollno = rollno;
          this.name = name;
          this.math = math;
          this.phy = phy;
          this.che = che;
      }
      student.prototype.calculate = function () {
          this.per = (this.math + this.phy + this.che) / 3;
          console.log(this.per);
      };
      student.prototype.display = function () {
          console.log(this.rollno + " " + this.name + " " + this.per);
      };
      return student;
  }());
  var stud = new student(1, "student_1", 67, 56, 78);
  stud.calculate();
  stud.display();
  //assign grade.-- program
  