Write a class Student() such that it has an attribute 'score' (that is initialized with 10) and three methods: add_score(): adds
10 to the score decrease_score(): decreases score by 10 __str__(): returns the current score (should return a string) Example:
1 answer:
Answer:
I am writing the Python program. Let me know if you want the program in some other programming language. Here is the Python code:
class Student(object):
def __init__(a,score=10):
a.score=score
def add_score(a,score):
a.score += 10
return (score)
def decrease_score(a,score):
a.score -=10
return (score)
def __str__(a):
current_score="{}".format(a.score)
return current_score
Explanation:
The program has a Student() class with attribute score.
It has the following methods:
__init__(): This method works as a constructor and enables to initialize score attribute of Student class. The value of score is initialized to 10. I have used a as the instance of Student class. However self keyword can also be used as an instance of the object to access the attributes and methods of Student class.
add_score() This method is used to add 10 to the score.
decrease_score() This method is used to decrease the score by 10.
__str__() This method is used to return the current score. format() is used here to return a string. current_score holds the value of the current score.
If you want the check the working of the program, then you can use the following statements to see the results on the output screen:
p = Student()
print(p)
p.add_score(p)
print(p)
This will create an object p of Student class and calls the above methods to display the values of the score according to the methods.
The program along with its output is attached.
You might be interested in
Answer:
Here is the C++ program:
#include <iostream> //to use input output functions
using namespace std; //to identify objects cin cout
int main(){ //start of main method
double risingLevel; //declares a double type variable to hold rising level
cin>>risingLevel; //reads the value of risingLevel from user
cout<<"Level: "<<risingLevel<<endl; //displays the rising level
cout << "Years: 5, Rise: " << risingLevel * 5<<endl; //displays the rise in ocean level over 5 years
cout << "Years: 10, Rise: " << risingLevel * 10<<endl; //displays the rise in ocean level over 10 years
cout << "Years: 50, Rise: " << risingLevel * 50<<endl; //displays the rise in ocean level over 50 years
}
Explanation:
The program works as follows:
Lets say the user enters rising level 2.1 then,
risingLevel = 2.1
Now the first print (cout) statement :
cout<<"Level: "<<risingLevel<<endl; prints the value of risingLevel on output screen. So this statement displays:
Level: 2.1
Next, the program control moves to the statement:
cout << "Years: 5, Rise: " << risingLevel * 5<<endl;
which computes the rise in ocean levels over 5 years by formula:
risingLevel * 5 = 2.1 * 5 = 10.5
It then displays the computed value on output screen. So this statement displays:
Years: 5, Rise: 10.5 Next, the program control moves to the statement:
cout << "Years: 10, Rise: " << risingLevel * 10<<endl;
which computes the rise in ocean levels over 10 years by formula:
risingLevel * 10 = 2.1 * 10 = 21
It then displays the computed value on output screen. So this statement displays:
Years: 10, Rise: 21
Next, the program control moves to the statement:
cout << "Years: 50, Rise: " << risingLevel * 50<<endl;
which computes the rise in ocean levels over 50 years by formula:
risingLevel * 50 = 2.1 * 50 = 105
It then displays the computed value on output screen. So this statement displays:
Years: 50, Rise: 105 Hence the output of the entire program is:
Level: 2.1 Years: 5, Rise: 10.5 Years: 10, Rise: 21 Years: 50, Rise: 105
The screenshot of the program and its output is attached.
