Problem:
Score : 300 points

Problem Statement

You are given four integers A, B, C, and D. Find the number of integers between A and B (inclusive) that can be evenly divided by neither C nor D.

Constraints

1\leq A\leq B\leq 10^{18}

1\leq C,D\leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C D

Output

Print the number of integers between A and B (inclusive) that can be evenly divided by neither C nor D.

Sample Input 1

4 9 2 3

Sample Output 1

2

5 and 7 satisfy the condition.

Sample Input 2

10 40 6 8

Sample Output 2

23

Sample Input 3

314159265358979323 846264338327950288 419716939 937510582

Sample Output 3

532105071133627368

Solution in JavaScript (node.js v5.12) (judge verdict: Time Limit Exceeded)

function main(input) {
  const inputList = input.split(/\s/).map(inp => formatNum(inp));
  const A = inputList[0];
  const B = inputList[1];
  const C = inputList[2];
  const D = inputList[3];
  
  // たぶんlte
  const list = [];
  for (var i = A; i <= B; i++) {
    list.push(i);
  }
  const retList = list
  	.filter(n => 0 !== n % C)
  	.filter(m => 0 !== m % D);
  console.log(retList.length);
};

// 文字列を数値に変換
function formatNum(str) {
  return Number(str);
};

main(require("fs").readFileSync("/dev/stdin", "utf8"));