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 <= 10^9
2 <= A <= 40000
2 <= B <= 40000
如果正整数可以被 A 或 B 整除,那么它是神奇的。返回第 N 个神奇数字。由于答案可能非常大,返回它模 10^9 + 7 的结果。
提示:
- 1 <= N <= 10^9
- 2 <= A <= 40000
- 2 <= B <= 40000
- 给出 3 个数字,a,b,n。要求输出可以整除 a 或者整除 b 的第 n 个数。
- 这一题是第 1201 题的缩水版,代码和解题思路也基本不变,这一题的二分搜索的区间是
[min(A, B),N * min(A, B)] = [2, 10 ^ 14]
。其他代码和第 1201 题一致,思路见第 1201 题。