第十四届蓝桥杯集训——练习解题阶段(无序阶段)-ALGO-51算法训练 Torry的困惑(基本型)

#include<stdio.h>

int pr[100010];
int top;

int isPrime(int n)
{
	int i;
	for(i = 0; i < top; i++)
	{
		if(n % pr[i] == 0)
		{
			return 0;
		}
	}
	return 1;
}

int findNextPrime(void)
{
	int n = pr[top - 1] + 1;
	while(!isPrime(n))
	{
		n++;
	}
	pr[top++] = n;
	return n;
}

int main(void)
{
	int i, n;
	int result = 2;
	scanf("%d", &n);
	pr[0] = 2;
	top = 1;
	for(i = 1; i < n; i++)
	{
		int x = findNextPrime();
		result *= x;
		result %= 50000;
	}
	printf("%d", result);
	return 0;
}

#include <iostream>

using namespace std;

int a[100005];

int main()
{
	unsigned int i, j, n, cnt = 1, cj = 2;

	cin >> n;

	if (n == 1)
	{
		cout << 2 << endl;
		return 0;
	}

	a[0] = 2;

	for (i = 3; i < 2000000; i++)
	{
		for (j = 0; j < cnt; j++)
		{
			if (a[j] * a[j] > i)
			{
				break;
			}
			else
			{
				if (!(i % a[j]))
				{
					break;
				}
			}
		}

		if (a[j] * a[j] > i)
		{
			a[cnt++] = i;

			cj = (cj % 50000) * (i % 50000) ;

			if (cnt == n)
			{
				break;
			}
		}
	}

	cout << cj % 50000 << endl;

	return 0;
}

import java.io.*;
public class Main {

	public static void main(String[] args) {
		try{
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in),1);
			String line = br.readLine();
			int n = Integer.parseInt(line);
			getans(n);
		}catch(Exception e){
			System.out.println("Message:"+e.getMessage());
		}		
	}
	
	public static void getans(int n){
		if(n<1);
		else if(n==1)System.out.println(2);
		else if(n<7){
			long ans = 6,nowp = 3;
			for(int i=0;i<n-2;i++){
				nowp=nextprime(nowp);
				ans*=nowp;
			}
			System.out.println(ans);
		}else if(n==7)System.out.println(10510);
		else if(n<100){
			long ans = 10510,nowp = 17;
			for(int i=0;i<n-7;i++){
				nowp=nextprime(nowp);
				ans=ans*nowp%50000;
			}
			System.out.println(ans);
		}else if(n==100)System.out.println(31090);
		else if(n<1000){
			long ans = 31090,nowp = 541;
			for(int i=0;i<n-100;i++){
				nowp=nextprime(nowp);
				ans=ans*nowp%50000;
			}
			System.out.println(ans);
		}else if(n==1000)System.out.println(1570);
		else if(n<=10000){
			long ans = 1570,nowp = 7919;
			for(int i=0;i<n-100;i++){
				nowp=nextprime(nowp);
				ans=ans*nowp%50000;
			}
			System.out.println(ans);
		}else if(n==10000)System.out.println(48410);
		else if(n<100000){
			long ans = 48410,nowp = 115321;
			for(int i=0;i<n-100;i++){
				nowp=nextprime(nowp);
				ans=nowp%50000*ans%50000;
			}
			System.out.println(ans);
		}else if(n==100000)System.out.println(20710);
		else{
			long ans = 20710,nowp = 1452433;
			for(int i=0;i<n-100;i++){
				nowp=nextprime(nowp);
				ans=nowp%50000*ans%50000;
			}
			System.out.println(ans);
		}
	}
	
	public static long nextprime(long now){
		now+=2;
		int check = 0;
		while(true){
			check = checkprime(now);
			if(check==0)
				now+=2;
			else
				break;
		}
		return now;
	}
	
	public static int checkprime(long n){
		for(int i=3;i<=Math.sqrt(n);i+=2)
			if(n%i==0)return 0;
		return 1;
	}
	
}

n=eval(input())
num=1
i=2
count=0
while True:
    flag=0
    for j in range(2,i):
        if i%j==0:
            flag=1
            break
    if flag==0:
        count+=1
        if num>50000:
            num%=50000
        num*=i
    if count==n:
        print(num%50000)
        break
    i+=1