813B - The Golden Age - CodeForces Solution

import math
import os
import random
import re
import sys


    


if __name__ == '__main__':
    
    x,y,l,r = list(map(int, input().rstrip().split()))
    
    arr = []
    a,b = 1,1

    while a<r:
        b = 1
        while a+b<=r:
            if l <= a+b and a+b <= r:
                arr.append(a+b)
            b *= y 
        a *= x
    ans = 0
    arr += [l-1,r+1]
    arr.sort()
        for i in range(1,len(arr)):
        ans = max(ans,arr[i]-arr[i-1]-1)
    print(ans)