Problem:
Score : 400 points

Problem Statement

Takahashi had a pair of two positive integers not exceeding N, (a,b), which he has forgotten.
He remembers that the remainder of a divided by b was greater than or equal to K.
Find the number of possible pairs that he may have had.

Constraints

1 \leq N \leq 10^5

0 \leq K \leq N-1

All input values are integers.

Input

Input is given from Standard Input in the following format:

N K

Output

Print the number of possible pairs that he may have had.

Sample Input 1

5 2

Sample Output 1

7

There are seven possible pairs: (2,3),(5,3),(2,4),(3,4),(2,5),(3,5) and (4,5).

Sample Input 2

10 0

Sample Output 2

100

Sample Input 3

31415 9265

Sample Output 3

287927211

Solution in JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

// inputに入力データ全体が入る
function Main(input) {
	var line = input.split("\n");
	var tmp = line[0].split(" ");
	var maxint = Number(tmp[0]);
	var minrest = Number(tmp[1]);
	var ans = 0;
	for(b = minrest + 1; b <= maxint; b++){
		var outsideLoop = ((maxint%b)-minrest+1 < 0) ? 0 : ((maxint%b)-minrest+1);
		ans += (b-minrest)*Math.floor(maxint/b) + outsideLoop;
	}
	console.log(ans);
}

//*この行以降は編集しないでください（標準入出力から一度に読み込み、Mainを呼び出します）
Main(require("fs").readFileSync("/dev/stdin", "utf8"));