program leapyear; { This program determines whether a year (entered by the user) is a leap year. } var year : integer; begin write('Enter a year: '); readln(year); if (year mod 4 = 0) and (year mod 100 <> 0) or (year mod 400 = 0) then writeln(year, ' is a leap year') else writeln(year, ' is NOT a leap year'); end.
After we compile the program into a executable named leapyear and then run the program, we get:
% leapyear Enter a year: 1997 1997 is NOT a leap year % leapyear Enter a year: 2000 2000 is a leap year