输入输出练习

记录一下常见的笔试输入输出的几种情况及代码实现

第一行输入一个整数n表示行数，接下来的n行都输入一个整数

Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
for (int i = 0; i < n; i++) {
    int num = scanner.nextInt();
}

也可以将n个整数存在数组当中

Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int[] nums = new int[n];
for (int i = 0; i < n; i++) {
    nums[i] = scanner.nextInt();
}

第一行输入一个整数n表示行数，接下来的n行分别输入多个整数，以空格分开

Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
scanner.nextLine(); // 消耗掉输入行末的换行符，否则按下回车键后程序报错
for (int i = 0; i < n; i++) {
    String line = scanner.nextLine();
    String[] str = line.split(" "); // 使用空格分割符串
    for (int j = 0; j < str.length; j++) {
        String s = str[j];
        int num = Integer.parseInt(s);
        System.out.print(num + " ");
    }
    System.out.println();
}

第一行输入一个整数n表示行数，接下来的n行输入不定长的字符串

Scanner scanner = new Scanner(System.in);
System.out.print("请输入行数n：");
int n = scanner.nextInt();
scanner.nextLine(); 
String[] str = new String[n]; 
for (int i = 0; i < n; i++) {
    str[i] = scanner.nextLine();
}