Pascal program to print prime numbers

Pascal program to print prime numbers

Prime numbers

The number that is divisible only by itself and 1.
Pascal program to print prime numbers between 1 and hundred.

 
{Program to print prime numbers between 1 and 100}
program PrimeNumber;
const
  Num=100;
var
  i,j:integer;
  prime:boolean;

begin
  i:=2;
  while i<=Num do
  begin
     j:=2;
     prime:=True;
     while j<i do {to make it efficient here can use j<=i/2 :Reason: last factor of any number is number itself one before last number is always less than half of the value  }
     begin
        if i mod j= 0 then
        begin
          prime:=False;
        end;
        j:=j+1;
     end;
     if prime=True then
     begin
       writeln(i);
     end;
     i:=i+1;
  end;
  writeln('Press Enter to Exit....');
  readln;
end.

Output of the above Pascal Program

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