Java学习习题_03

题目链接：https://pan.baidu.com/s/1zZoDx3o6GJmgrezMxhMjHg

提取码：krnr

package question_03; import java.util.*; public class question_03_1 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); int m = x.nextInt(); System.out.println(add(n,m)); } public static int add(int a,int b){ int c = a+b; return c; } }

package question_03; import java.util.*; public class question_03_2 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); yinzi(n); } public static void yinzi(int n){ for(int i=1; i<=n; i++) { if(n%i == 0) { System.out.print(i+" "); } } } }

3.

package question_03; import java.util.Scanner; public class question_03_3 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); System.out.println(sum(n)); } public static int sum(int n){ int result=0; for(int i=1; i<=n; i++) { result += i; } return result; } }

package question_03; import java.util.Scanner; public class question_03_4 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); shuChu(n); } public static void shuChu(int n){ for(int i=1; i<=n; i++) { System.out.println("HelloWorld"); } } }

5.

package question_03; import java.util.Scanner; public class question_03_5 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); System.out.println(fanHui(n)); } public static int fanHui(int n){ int sum = 0; while(n>0) { n/=10; sum+=1; } return sum; } }

package question_03; public class question_03_6 { public static void main(String[] args) { for(int n=100; n<1000; n++) { int a = n/100; int b = n/10%10; int c = n%10; if(n == result(a) + result(b) + result(c)) { System.out.println(n); } } } public static int result(int n){ if(n == 0) { return 1; } else { return n*result(n-1); } } }

package question_03; public class question_03_7 { public static void main(String[] args) { for(int i=1; i<3000; i++) { if(factorSum(factorSum(i)) == i) { System.out.println(i); } } } public static int factorSum(int n){ int sum=0; for(int i=1; i<n; i++) { if(n%i == 0) { sum+=i; } } return sum; } }

package question_03; import java.util.Scanner; public class question_03_8 { public static void main(String[] args) { Scanner x = new Scanner(System.in); int n = x.nextInt(); for(int i=2; i<=n/2; i++) { if(judge(i) == 1 && judge(n-i) == 1) System.out.println(n+"="+i+"+"+(n-i)); } } public static int judge(int n){ for(int i=2; i<n; i++) { if(n%i == 0) { return 0; } } return 1; } }