洛谷oj题单【入门1】顺序结构-入门难度（Java）

来源：https://www.luogu.com.cn/training/100#problems

B2002 Hello,World!

public class Main { public static void main(String[] args){ System.out.println("Hello,World!"); } }

B2025 输出字符菱形

public class Main { public static void main(String[] args){ System.out.println(" * "); System.out.println(" *** "); System.out.println("*****"); System.out.println(" *** "); System.out.println(" * "); } }

P1001 A+B Problem

import java.util.Scanner; public class Main { public static void main(String[] args){ Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int c = a+b; System.out.println(c); } }

B2005 字符三角形

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); String s = sc.next(); System.out.println(" "+s+" "); System.out.println(" "+s+s+s+" "); System.out.println(s+s+s+s+s); } }

B5703 【深基2.例5】苹果采购

import java.util.Scanner; public class Main { public static void main(String[] args) { // 现在需要采购一些苹果    
    
    
    
 ，每名同学都可以分到固定数量的苹果     


     


     


     


     ，并且已经知道了同学的数量




 




 




 




 




，请问需要采购多少个苹果？/ Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int apple = a * b; System.out.println(apple); } }

P5704 【深基2.例6】字母转换

import java.util.Scanner; public class Main { public static void main(String[] args) { // 输入一个小写字母
   

   

   

   

，输出其对应的大写字母    
    
    
    
 。例如输入 q[回车] 时     

     

     

     

     ，会输出 Q     


     


     


     


     。/ Scanner sc = new Scanner(System.in); char a = sc.next().charAt(0); char b = (char) (a - 32); System.out.println(b); } }

P5705 【深基2.例7】数字反转

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); double num = sc.nextDouble(); int n = (int)(num * 10); double temp = 0; while(n != 0){ //这里的n必须为int类型 




  




  




  




  



，若为double或float

  


  


  


  


，n可无限趋近于0 temp = n % 10 + temp * 10; n /= 10; } System.out.printf("%.3f",temp/1000); } }

P5706 【深基2.例8】再分肥宅水

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); float t = sc.nextFloat(); int n = sc.nextInt(); float a = t/n; int b = 2*n; System.out.printf("%.3f",a); System.out.println(); System.out.println(b); } }

P5708 【深基2.习2】三角形面积

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); double a = sc.nextDouble(); double b = sc.nextDouble(); double c = sc.nextDouble(); double p = (a + b + c) / 2.0; Math.sqrt(p*(p-a)*(p-b)*(p-c)); System.out.printf("%.1f",Math.sqrt(p*(p-a)*(p-b)*(p-c))); } }

B2029 大象喝水

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int h = sc.nextInt(); int r = sc.nextInt(); int a = 20 * 1000; double b = 3.14 * r * r * h ; int n = (int)Math.ceil(a/b); System.out.println(n); } }

P1425 小鱼的游泳时间

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int c = sc.nextInt(); int d = sc.nextInt(); int x = c - a; int y = d - b; if(y < 0){ x--; y = d + 60 - b; } System.out.print(x + " "); System.out.print(y); } }

P1421 小玉买文具

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int x = a * 10 + b; int y = 1 * 10 + 9; int res = (int)Math.floor(x/y); System.out.println(res); } }

P3954 [NOIP2017 普及组] 成绩

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int a = sc.nextInt(); int b = sc.nextInt(); int c = sc.nextInt(); int res = (int) (a * 0.2 + b * 0.3 + c * 0.5); System.out.println(res); } }