Counter Strike [JavaScript]

function counterStrike(input) {
    let initialEnergy = Number(input.shift());

    let wonBattlesCounter = 0;
    let index = 0;

    while (input[index] !== "End of battle") {
        let distance = Number(input[index]);

        if (initialEnergy < distance) {
            console.log(`Not enough energy! Game ends with ${wonBattlesCounter} won battles and ${initialEnergy} energy`);
            return;
        }

        wonBattlesCounter++;
        initialEnergy -= distance;

        if (wonBattlesCounter % 3 == 0) {
            initialEnergy += wonBattlesCounter;
        }

        index++;
    }

    console.log(`Won battles: ${wonBattlesCounter}. Energy left: ${initialEnergy}`);
}