workout.js

function workout(input) {
    let index = 0;
    let days = Number(input[index]);
    index++;
    let startDistance = Number(input[index]);
    index++;
    let distance = startDistance;

    for (let i = 0; i < days; i++) {
        let dailyNormInc = Number(input[index]) / 100;
        index++;
        startDistance += (startDistance * dailyNormInc);
        distance += startDistance;
    }

    if (distance >= 1000) {
        console.log(`You've done a great job running ${Math.ceil(distance - 1000)} more kilometers!`);
    } else {
        console.log(`Sorry Mrs. Ivanova, you need to run ${Math.ceil(1000 - distance)} more kilometers`);
    }
}

workout(["4", "100", "30", "50", "60", "80"]);