Two Arithmetic Progressions

已知两个无限长的等差数列，首项分别为 $b_1, b_2$，公差分别为 $a_1, a_2$，求 $[L,R]$ 中有多少个数在两个等差数列中都出现了。

You are given two arithmetic progressions: $ a_{1}k+b_{1} $ and $ a_{2}l+b_{2} $ . Find the number of integers $ x $ such that $ L<=x<=R $ and $ x=a_{1}k'+b_{1}=a_{2}l'+b_{2} $ , for some integers $ k',l'>=0 $ .

The only line contains six integers $ a_{1},b_{1},a_{2},b_{2},L,R \, ( 0 \lt a_1,a_2 \le 2\times10^9,-2\times10^9 \le b_1,b_2,L,R \le 2\times10^9,L \le R)$ .

Print the desired number of integers $ x $ .

2 0 3 3 5 21

3

2 4 3 0 6 17

2