13. Prime Pairs

function  primePairs(input) {
    let firstStart = Number(input[0]);
    let secondStart = Number(input[1]);
    let firstDiff = Number(input[2]);
    let secondDiff = Number(input[3]);

    for (let i = firstStart; i <= firstStart + firstDiff; i++) {
        for (let j = secondStart; j <= secondStart + secondDiff; j++) {
            let isFirstPrime = true;
            let isSecondPrime = true;

            for (let k = 2; k <= Math.sqrt(i); k++) {
                if (i % k === 0) {
                    isFirstPrime = false;
                    break;
                }
            }
            for (let k = 2; k <= Math.sqrt(j); k++) {
                if (j % k === 0) {
                    isSecondPrime = false;
                    break;
                }
            }
            if (isFirstPrime && isSecondPrime) {
                console.log(`${i}${j}`);
            }
        }
    }
}