ScrollingText

public class test {
	public static long LCM(long a,long b)	//Function to find LCM
	{
	long num1=a,num2=b;
	while(a!=b)
	{
		if(a<b)
		{
			a+=num1;
		}
		else
		{
			b+=num2;
		}
	}
	return a;
	}
public static void main(String args[]){
	long num = 1;
	int limit = 20; //This is the limit,you can change it to whatever you want.
	int i=2;	//Initializing i to 2
	System.out.println("This program will find out the least number which is divisible by 1-20.");
	while(i<limit)	//While loop executes till i reaches the limit.
	{
		num=LCM(num,i);	//Calling LCM function to calculate the LCM of the current'num' and 'i'
		i++;	//Incrementing i
	}
	System.out.println("The answer is: "+num);	//Prints the final answer.
 
}//End of main
}//End of class

use List::MoreUtils qw( all );
 
for(my $x = 2520; ; $x += 2520) {
  print "$x\n" and last if all { $x % $_ == 0 } 11 .. 20;
}

#!/usr/bin/python3
 
def gcd(a,b):
    if b>a: return gcd(b,a)
    if b == 0: return a
    return gcd(b, a-b*(a//b))
 
def lcm(a,b):
    return abs(a*b)//gcd(a,b)
 
def maxLcm(num):
    prod = 1
    for i in range(1,num+1):
        prod = lcm(i,prod)
    return prod
 
print(maxLcm(20))

from collections import defaultdict
import operator
from itertools import starmap
 
primes = [2,3,5,7,11,13,17,19]
 
def factor(n):
    factors = defaultdict(int)
    p = 0
    while n > 1:
        if n % primes[p] == 0:
            n /= primes[p]; factors[primes[p]]+=1
        else:
            p+=1
    return factors
 
def gf(n):
    factors = defaultdict(int)
    for i in range(n):
        ifact = factor(i)
        for p,c in ifact.iteritems():
            if factors[p] < c: factors[p] = c
    return reduce(operator.mul,starmap(pow, factors.items()))
 
 if __name__== '__main__':
    print gf(20)

#!/usr/bin/perl
sub gcd { 
  my($a,$b,@r)=@_; 
  @r ? gcd($a,gcd($b,@r)): $b==0 ? $a : gcd($b, $a%$b) 
}
sub lcm { 
  my($a,$b,@r)=@_; 
  @r ? lcm($a,lcm($b,@r)) : $a*$b/gcd($a,$b) 
}
 
print lcm(1..20), "\n";
#prints: 232792560

result = foldl lcm 1 [1 .. 20]