A positive integer is magical if it is divisible by either A or B.
Return the N-th magical number. Since the answer may be very large, return it modulo 10^9 + 7.
Example 1:
Input: N = 1, A = 2, B = 3 Output: 2
Example 2:
Input: N = 4, A = 2, B = 3 Output: 6
Example 3:
Input: N = 5, A = 2, B = 4 Output: 10
Example 4:
Input: N = 3, A = 6, B = 4 Output: 8
Note:
1 <= N <= 10^92 <= A <= 400002 <= B <= 40000
[Math] [Binary Search]