Java - 阅读输入 - 似乎不起作用？

Question

这是我的代码片段：

public static void main(String[] args) {
    System.out.println("This is the square root game. Only two players allowed.");

    Scanner scan = new Scanner(System.in);
    System.out.println("How many rounds are you two playing?");
    int numofRounds = scan.nextInt();

    System.out.println("First player, what is your name?");
    String firstPlayer = scan.nextLine();
    System.out.println();

    System.out.println("Second player, what is your name?");
    String secondPlayer = scan.nextLine();
    System.out.println();

一切正常：它读入numofRounds的下一个整数，并在nextPlayer的下一行读取，但它完全跳过firstPlayer，不允许我为它输入。为什么是这样？在此先感谢：）

谢谢！