【牛客-输入输出练习】

1 只有输出

import java.util.Scanner;// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {public static void main(String[] args) {System.out.println("Hello Nowcoder!");}
}

2 单组_A+B

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

3 多组_A+B_EOF形式

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

4 多组_A+B_T组形式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner=new Scanner(System.in);int count=scanner.nextInt();int [] arr=new int[count];for (int i=1;i<=count;i++){int a=scanner.nextInt();int b=scanner.nextInt();arr[i-1]=a+b;}for (int i=0;i<count;i++){System.out.println(arr[i]);}}
}

5 多组_A+B_零尾模式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);while (true) {int a = scanner.nextInt();int b = scanner.nextInt();if (a == 0 && b == 0) {break;}System.out.println(a+b);}}
}

6 单组_一维数组

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n= scanner.nextInt();int [] arr=new int [n];Long sum=0L;for (int i = 0; i < n; i++) {arr[i]=scanner.nextInt();sum+=arr[i];}System.out.println(sum);}
}

7 多组_一维数组_T组形式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n = scanner.nextInt();while (n-->0){int a = scanner.nextInt();int [] arr=new int[a+5];Long sum=0L;for (int i = 0; i < a; i++) {arr[i] = scanner.nextInt();sum+=arr[i];}System.out.println(sum);}}
}

8 单组_二维数组

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int a=scanner.nextInt();int b=scanner.nextInt();int [][]arr=new int[a][b];Long sum=0L;for (int i = 0; i < a; i++){for (int j = 0; j < b; j++){arr[i][j]=scanner.nextInt();sum+=arr[i][j];}}System.out.println(sum);}
}

9 多组_二维数组_T组形式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n=scanner.nextInt();while (n-->0){int a=scanner.nextInt();int b=scanner.nextInt();int [][]arr=new int[a][b];Long sum=0L;for (int i = 0; i < a; i++){for (int j = 0; j < b; j++){arr[i][j]=scanner.nextInt();sum+=arr[i][j];}}System.out.println(sum);}}
}

10 单组_字符串

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n=scanner.nextInt();char [] arr=new char[n];String str=scanner.next();for (int i=0;i<n;i++){arr[i]=str.charAt(i);}//字符串逆置for (int i=n-1;i>=0;i--){System.out.print(arr[i]);}}
}

11 多组_字符串_T组形式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int count=scanner.nextInt();while (count-->0){int n=scanner.nextInt();char [] arr=new char[n];String str=scanner.next();for (int i=0;i<n;i++){arr[i]=str.charAt(i);}StringBuilder sb=new StringBuilder();for (int i=n-1;i>=0;i--){sb.append(arr[i]);}System.out.println(sb.toString());}}
}

12 单组_二维字符数组

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n = scanner.nextInt();// 消耗换行符scanner.nextLine();StringBuilder[] arr = new StringBuilder[n];for (int i = 0; i < n; i++) {String s = scanner.nextLine();StringBuilder sb = new StringBuilder(s);sb.reverse();arr[i] = sb;}for (int i = n-1; i >=0; i--){System.out.println(arr[i]);}}
}

13 多组_带空格的字符串_T组形式

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int count=scanner.nextInt();while (count-->0){int n = scanner.nextInt();//消耗掉换行符scanner.nextLine();String s = scanner.nextLine().replaceAll(" ","");StringBuilder sb = new StringBuilder(s);sb.reverse();System.out.println(sb);}}
}

14 单组_保留小数位数

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);double count=scanner.nextDouble();//保留3位小数System.out.printf("%.3f",count);}
}

15 单组_补充前导零

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int number=scanner.nextInt();String formattedNumber = String.format("%09d", number);System.out.println(formattedNumber);}
}

16 单组_spj判断YES与NO

import java.util.Scanner;public class Main{public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int number = scanner.nextInt();if (number % 2 == 0) {System.out.println("NO");} else {System.out.println("YES");}}
}

17 单组_spj判断浮点误差

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int r = scanner.nextInt();System.out.println(Math.pow(r,2)*Math.PI);}
}

18 单组_spj判断数组之和

import java.util.Arrays;
import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);int n = scanner.nextInt();int m = scanner.nextInt();if (m % n == 0) {for (int i = 0; i < n; i++) {System.out.print(m / n + " ");}} else {int[] result = constructArray(n, m);for (int i = 0; i < result.length; i++) {System.out.print(result[i] + " ");}}}public static int[] constructArray(int n, int m) {// 2. 初始化数组（每个元素至少为1）int[] arr = new int[n];Arrays.fill(arr, 1);// 3. 计算剩余需要分配的值int remaining = m - n;// 4. 分配剩余值（均匀分配）int index = 0;while (remaining > 0) {arr[index % n] += 1;remaining--;index++;}return arr;}
}