14. 员工派遣

const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});

rl.on('line', (line) => {
    const [x,y,cntX,cntY] = line.split(' ').map(Number);
    let minId = cntX + cntY;
    let maxId = 1000000000;
    while(minId <= maxId) {
        const midId = Math.floor((maxId + minId)/2);
        const excludedX = Math.floor(midId/x);
        const excludedY = Math.floor(midId/y);
        const needx = Math.max(0, cntX - (excludedY - excludedBoth));
        const needy = Math.max(0, cntY - (excludedX - excludedBoth));
        const excludedBoth = Math.floor(midId/(x*y));
        const total = midId - excludedX - excludedY + excludedBoth;
        if (needx + needy <= total) {
            maxId = midId - 1;
        } else {
            minId = midId + 1;
        }
    }
    console.log(minId);
});