蓝桥杯练习题库——基础练习（更新中）

方法一：

import java.math.BigInteger;
import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int n=scan.nextInt();
		BigInteger s=BigInteger.ONE;
		for(int i=1;i<=n;i++)
			s=s.multiply(BigInteger.valueOf(i));
		System.out.println(s);
		scan.close();
	}
}

方法二：

import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int n=scan.nextInt();
		scan.close();
		int[] a=new int[3000];
		a[2999]=1;
		int p=2999,rem=0;
		for(int i=2;i<=n;i++)
		{
			while(p>0)
			{
				int sum=a[p]*i+rem;
				rem=0;
				if(sum>9)
				{
					a[p]=sum%10;
					rem=sum/10;
				}
				else
				{
					a[p]=sum;
				}
				p--;
			}
			p=2999;
			rem=0;
		}
		int flag=0;
		for(int i=0;i

import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		String s1=scan.nextLine();
		String s2=scan.nextLine();
		scan.close();
		int[] a=new int[102];
		int[] b=new int[102];
		int[] c=new int[102];
		int cnt=0;
		for(int i=s1.length()-1;i>=0;i--)
		{
			a[cnt++]=Integer.parseInt(String.valueOf(s1.charAt(i)));
		}
		cnt=0;
		for(int i=s2.length()-1;i>=0;i--)
		{
			b[cnt++]=Integer.parseInt(String.valueOf(s2.charAt(i)));
		}
		int rem=0;
		for(int i=0;i9)
			{
				c[i]=sum%10;
				rem=sum/10;
			}
			else
			{
				c[i]=sum;
				rem=0;
			}
		}
		int count=0;
		for(int i=c.length-1;i>=0;i--)
		{
			if(c[i]!=0||count==1)
			{
				System.out.print(c[i]);
				count=1;
			}
		}
	}
}

Huffman树

import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int n=scan.nextInt();
		Queue a=new PriorityQueue();
		for(int i=0;i

import java.util.*;

class Main{
	static int[][] x;//二维数组创建棋盘
	static int sum=0;//用于记录放法数目
	static int n;//棋盘的大小
	public static void main(String[] args)
	{
		Scanner sc=new Scanner(System.in);
		n=sc.nextInt();
		x=new int[n][n];
		for(int i=0;i

import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int h=scan.nextInt();
		int m=scan.nextInt();
		String[] a=new String[] {"zero","one","two","three","four","five","six","seven","eight","nine","ten",
				"eleven","twelve","thirteen","fourteen","fifteen","sixteen","seventeen","eighteen",
				"nineteen","twenty"};
		String[] b=new String[] {"twenty","thirty","forty","fifty"};
		if(h<=20) System.out.print(a[h]+" ");
		else
		{
			h=h%20;
			System.out.print(a[20]+" "+a[h]+" ");
		}
		if(m>20)
		{
			int w=m/10;
			int r=m%10;
			System.out.print(b[w-2]+" ");
			if(r!=0) System.out.print(a[r]+" ");
			System.out.print("o`clock");
		}
		else if(m<=20&&m!=0)
		{
			System.out.print(a[m]+" ");
			System.out.print("o`clock");
		}
		else
		{
			System.out.print("o`clock");
		}
	}
}

import java.util.*;

class Main{
	final static int INF=(int) Double.POSITIVE_INFINITY;
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int m=scan.nextInt();
		int n=scan.nextInt();
		int[][] a=new int[m][n];
		for(int i=0;i=0&&a[r][c]!=INF)
				{
					System.out.print(a[r][c]);
					sum++;
					if(sum!=m*n) System.out.print(" ");
					a[r][c]=INF;
					r--;
				}
				r++;mark++;c--;
			}
			if(mark%4==3)
			{
				while(c>=0&&a[r][c]!=INF)
				{
					System.out.print(a[r][c]);
					sum++;
					if(sum!=m*n) System.out.print(" ");
					a[r][c]=INF;
					c--;
				}
				r++;mark++;c++;
			}
		}
	}
}

import java.util.*;

class Main{
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int v1=scan.nextInt();
		int v2=scan.nextInt();
		int t=scan.nextInt();
		int s=scan.nextInt();
		int l=scan.nextInt();
		scan.close();
		int stu=0,swu=0;
		int i=0;
		while(stu=t)
			{
				swu+=s*v2;
				i+=s;

			}
			else
			{
				stu+=v1;
				i++;
				swu+=v2;
			}
			if(stu>=l&&swu=l&&swu>=l)
				System.out.println("D");
			else if(swu>=l&&stu

import java.util.*;

class Main {
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int L=scan.nextInt();
		String s=scan.next();
		int max=0;
		String smax="";
		Map map=new HashMap<>();
		for(int i=0;imax)
					{
						max=value;
						smax=s1;
					}
					else if(max==value)
					{
						if(s1.length()>smax.length())
							smax=s1;
					}
					map.put(s1, value);
				}
				else
					map.put(s1,1);
			}
		System.out.println(smax);
	}
}

import java.util.*;

class Main {
	public static void main(String[] args)
	{
		Scanner scan=new Scanner(System.in);
		int n=scan.nextInt();
		scan.close();
		digui(n);
	}
	static void digui(int n)
	{
		String s=Integer.toBinaryString(n);
		int j=s.length()-1;//7
		boolean flag=true;
		for(int i=0;i2)
				{
					for(int k=i+1;k