How do You Write a PROLOG Program to Find Leap Year?

predicates
    run
    check_year(integer)
    
clauses
    run if
    write("Enter the year"), n1,
    readint(y),
    check_year(y),
    write("This is a leap year"), n1.
run if
    write("This is not a leap year"), n1.
    check_year(y) if
    0=y mod 4, 0<>y mod 100;
    0=y mod 400.

Output:

goals:  run
        Enter the year: 2020
        "This is a leap year"