洛谷官方题单[Java版题解]--【入门1】顺序结构

一.[入门1]顺序结构1.B2002 Hello,World!废话不多说,直接打印即可,代码如下import java.util.*; import java.io.*; public class Main{ public static void main(String[]args ){ System.out.println( * ); System.out.println( *** ); System.out.println(*****); System.out.println( *** ); System.out.println( *); } }2.B2025 输出字符菱形废话不多说,直接打印即可,代码如下:import java.util.*; import java.io.*; public class Main{ public static void main(String[]args ){ System.out.println( * ); System.out.println( *** ); System.out.println(*****); System.out.println( *** ); System.out.println( *); } }3.P1000 超级玛丽游戏public class Main { public static void main(String[] args) { System.out.println( ********); System.out.println( ************); System.out.println( ####....#.); System.out.println( #..###.....##....); System.out.println( ###.......###### ### ###); System.out.println( ........... #...# #...#); System.out.println( ##*####### #.#.# #.#.#); System.out.println( ####*******###### #.#.# #.#.#); System.out.println( ...#***.****.*###.... #...# #...#); System.out.println( ....**********##..... ### ###); System.out.println( ....**** *****....); System.out.println( #### ####); System.out.println( ###### ######); System.out.println(##############################################################); System.out.println(#...#......#.##...#......#.##...#......#.##------------------#); System.out.println(###########################################------------------#); System.out.println(#..#....#....##..#....#....##..#....#....#####################); System.out.println(########################################## #----------#); System.out.println(#.....#......##.....#......##.....#......# #----------#); System.out.println(########################################## #----------#); System.out.println(#.#..#....#..##.#..#....#..##.#..#....#..# #----------#); System.out.println(########################################## ############); } }4.P1001 AB Problem 题解import java.util.*; import java.io.*; public class Main{ public static void main(String[] args ){ Scanner sc new Scanner(System.in); int a0;int b0; asc.nextInt(); bsc.nextInt(); int cab; System.out.println(c); } }5.B2005 字符三角形直接拼接即可 ,没有什么可说的,然后这里和c不同的是,这里不能输入单个char字符你可以使用charAt(0)直接去读取(sc.next().charAt(0));import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scnew Scanner(System.in); String a; asc.next(); System.out.println( a ); System.out.println( aaa ); System.out.println(aaaaa); } }6.P5703 【深基2.例5】苹果采购直接两个数相乘即可import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scnew Scanner(System.in); int a0;asc.nextInt(); int b0;bsc.nextInt(); System.out.println(a*b); } }7.P5704 【深基2.例6】字母转换import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scnew Scanner(System.in); char asc.next().charAt(0); //相减的原理是背后的Ascll码, //记住几个简单的即可, //a:97 A:65(相差32) //0:48 System.out.println((char)(a-32)); } }8.P5705 【深基2.例7】数字反转当然这个写法肯定是不行的,笑哭了.对着答案编译这块.import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scnew Scanner(System.in); //这道题最简单的写法,就是输入单个char字符,然后反向输出即可 //123.4 4.321-- String sc1; sc1sc.next(); char asc1.charAt(0); char bsc1.charAt(1); char csc1.charAt(2); char dsc1.charAt(3); char esc1.charAt(4); System.out.print(e); System.out.print(d); System.out.print(c); System.out.print(b); System.out.print(a); } }9.P5706 【深基2.例8】再分肥宅水知识点:四舍五入保留小数//然后如果你想保留小数(),这里是四舍五入的方式 //double a3.1415926 //可以用System.out.printf(%.2f,a),3.14import java.util.Scanner; public class Main { public static void main(String[] args) { //然后如果你想保留小数(),这里是四舍五入的方式 //double a3.1415926 //可以用System.out.printf(%.2f,a),3.14 double a;int b; Scanner sc new Scanner(System.in); a sc.nextDouble(); bsc.nextInt(); double res1a/b; System.out.printf(%.3f,res1); System.out.println(); System.out.println(b*2); } }