小编Ang*_*era的帖子

如何从数组中选择一个值？这个例子就是String[] ans = {"+", "-", "/", "*"};我要选择的"+".

public static void main(String[] args) {
    String[] ans = {"+","-","/","*"};
    Random random = new Random();
    Scanner calcu = new Scanner(System.in);
    System.out.print("Enter First number: ");
    numOne = calcu.nextInt();
    System.out.print("Enter Second number: ");
    numTwo = calcu.nextInt();
    System.out.print("Choose an Operator to use");

}

例如我想搜索代码A25和A29那么它会​​打印出来吗？我似乎找不到在arraylist中搜索长单词的语法.

    ArrayList<String> arrList = new ArrayList<String>();
    arrList.add("A25            CS 212          Data Structures         3");
    arrList.add("A26            IT 312          Data Base Management System 2   3");
    arrList.add("A27            IT 312          Data Base Management System 2   3");
    arrList.add("A28            IT 212          Data Base Management System 2   3");
    arrList.add("A29            CS 313          Digital Design          3");
    arrList.add("A30            IT 212          Discrete Structures     3");
    arrList.add("A25            IT 212          Discrete Structures     3");
    arrList.add("984            Engl 3          Speech and oral Communication   3");
    arrList.add("582            Theo 3          Christ and Sacraments       3");
    arrList.add("470            Stata1          Probablility and Statistics 3");
    arrList.add("999            Dota …