Java- 10-输入和输出_system.out.println(please input)-优快云博客

本文详细介绍Java中使用Scanner类进行输入操作，包括基本的数据类型读取，以及如何使用System.out.println, System.out.print和System.out.printf进行输出，特别是格式化输出的方法。通过实例展示了如何计算考试成绩的百分比提升，并格式化输出。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

输入

Scanner scanner = new Scanner(System.in);

输出

System.out.println()
System.out.print()
System.out.printf()

格式化输出：

System.out.printf("%s improved %.1f %%", "Argument1", 25.5f);

JDK字符串格式化参数说明：

https://docs.oracle.com/javase/8/docs/api/java/util/Formatter.html#syntax

import java.util.Scanner;

public class Hello{
	
	public static void main(String[] args) {
		System.out.println("please input the name:");
		Scanner scanner =  new Scanner(System.in);
		String name = scanner.nextLine();
		System.out.println("please input the age:");
		int age = scanner.nextInt();
		System.out.println("Hi, " + name + ", you are " + age);
		
	}
}

import java.util.Scanner;

public class Hello{
	
	public static void main(String[] args) {
		Scanner scanner =  new Scanner(System.in);
		
		System.out.println("please input the score for last exam:");
		int lastScore = scanner.nextInt();
		System.out.println("please input the score for this exam:");
		int thisScore = scanner.nextInt();
		
		double percentImprove = (thisScore - lastScore)*1.0/lastScore * 100;
		System.out.printf("the score improvement by percentage is %.2f%%", percentImprove);
		
	}
}