Java强训day4（选择题编程题）

选择题
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接口中的方法是为了让重写

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编程题
题目

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import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner sc = new Scanner(System.in);int a_b = sc.nextInt();int b_c = sc.nextInt();int ab = sc.nextInt();int bc = sc.nextInt();for(int i = -100;i<=100;i++) {for(int j = -100;j<=100;j++) {for(int k = -100;k<=100;k++) {if((i-j) == a_b) {if((j-k) == b_c) {if((i+j) == ab) {if((j+k) == bc) {System.out.print(i+" "+j+" "+k);return ;}}}}}}}System.out.println("No");sc.close();}
}

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner sc = new Scanner(System.in);int a = sc.nextInt();//A-Bint b = sc.nextInt();//B-Cint c = sc.nextInt();//A+Bint d = sc.nextInt();//B+Cint A = (a+c)/2;int B = (b+d)/2;int C = B-b;if((A-B)!=a || (B-C)!=b || (A+B)!=c || (B+C)!=d)System.out.println("No");elseSystem.out.println(A+" "+B+" "+C);sc.close();}
}

题目2
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import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner sc = new Scanner(System.in);int m = sc.nextInt();int n = sc.nextInt();StringBuffer s = new StringBuffer();String res = "0123456789ABCDEF";boolean f = false;if(m == 0){System.out.println(0);return ;}if(m<0) {m = -m;f = true;}while(m!=0) {s.append(res.charAt(m%n));m/=n;}if(f) {s.append('-');}System.out.println(s.reverse());sc.close();}
}