I created a problem, which I can't solve. Can anyone give answers? Thx :)

Time limit : 2s Given x, y, how many numbers can be represented as a * b, which 1 <= a <= x and 1 <= b <= y? (1 <= x, y <= 2e5)

Sample Input 2 5

Sample Output 8

Explanation Among 1 to 10, only 7 and 9 can't be written as a * b.