算法

Author: codeinmyself

.project

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+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Algorithm40</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

.settings/org.eclipse.jdt.core.prefs

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+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=1.8
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
+org.eclipse.jdt.core.compiler.source=1.8

bin/ConditionUse.class

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+import java.util.Scanner;
+
+public class ConditionUse {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+
+		System.out.println("input the score:");
+		Scanner sc=new Scanner(System.in);
+		int score=sc.nextInt();
+		evaluate(score);
+		sc.close();
+		System.exit(0);
+		
+		
+	}
+	
+	public static void evaluate(int score){
+		String str=(score>90?"A":(score>60?"B":"C"));
+		System.out.println(str);
+	}
+
+}

bin/Daffodil.class

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+/*
+ * 打印出所有的 "水仙花数 "，所谓 "水仙花数 "是指一个
+ * 三位数，其各位数字立方和等于该数本身。例如：153是一个 "水仙花数 "，因为153=1的三次方＋5的三次方＋3的三次方。
+ */
+public class Daffodil {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		System.out.println("hh");
+		MyMath mymath=new MyMath();
+		for(int i=100;i<1000;i++){
+			if(mymath.isDaffodil(i)==true)
+				System.out.println(i);
+		}
+	
+
+	}
+}
+class MyMath{
+	public  boolean isDaffodil(int number){
+		int s=0;
+		int count=0;
+		while(number!=0){
+			s= number%10;
+			count=count+s*s*s;
+			number=number/10;
+		}
+		return count==number;
+	}
+}

bin/MyMath.class

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+import java.util.Scanner;
+
+public class PrimeDivide {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+
+		Scanner sc=new Scanner(System.in);
+		System.out.println("input the number:");
+		int number=sc.nextInt();
+		divide(number);
+		sc.close();
+	}
+
+	public static void divide(int number){
+		for(int i=2;i<=number/2;i++){
+			while(number%i==0){
+				number/=i;
+				System.out.print(i+"*");
+			}
+		}
+		System.out.print(number);
+	}
+	
+}

bin/PrimeDivide.class

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+/*
+ * 判断101-200之间有多少个素数，并输出所有素数。 
+ */
+public class PrimeNumber {
+	public static void main(String[]args){
+		int primeNumber=0,index=0;
+		int a[]=new int[100];
+		for(int i=101;i<=200;i++){
+			if(isPrime(i)==true){
+				primeNumber++;
+			a[index]=i;
+			index++;
+			}
+		}
+		System.out.println(primeNumber);
+		for(int i=0;i<index;i++)
+			System.out.println(a[i]);
+	}
+	
+	public static boolean isPrime(int number){
+		boolean primeflag=true;
+		for(int i=2;i<=Math.sqrt(number);i++){
+			if(number%i==0){
+				primeflag=false;
+				break;
+			}
+		}
+		return primeflag;
+	}
+}

bin/PrimeNumber.class

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+/*
+ * 题目：古典问题：有一对兔子，从出生后第3个月起每个月都生一对兔子，小兔子长到第四
+ * 个月后每个月又生一对兔子，假如兔子都不死，问每个月的兔子总数为多少？ 
+ */
+
+public class RabbitBirth {
+	public static void main(String[] args){
+		int month=1;
+		for(int i=1;i<20;i++){
+			System.out.println(FeiBoCount(month));
+			month++;
+		}
+	}
+	
+	public static int FeiBoCount(int month){
+		if(month==1||month==2)
+			return 1;
+		else
+			return FeiBoCount(month-1)+FeiBoCount(month-2);
+		
+	}
+
+}
+