Prime Palindrome Golf Do you know how to play Prime Palindrome Golf? You are given a number and your challenge is to find the closest palindromic prime number that greater than what you were given. A palindromic number or numeral palindrome is a numb…

Find the smallest prime palindrome greater than or equal to N. Recall that a number is prime if it's only divisors are 1 and itself, and it is greater than 1.  For example, 2,3,5,7,11 and 13 are primes. Recall that a number is a palindrome if it read…

Find the smallest prime palindrome greater than or equal to N. Recall that a number is prime if it's only divisors are 1 and itself, and it is greater than 1. For example, 2,3,5,7,11 and 13 are primes. Recall that a number is a palindrome if it reads…

866. Prime Palindrome(回文素数) 题目: 求出大于或等于 N 的最小回文素数. 回顾一下,如果一个数大于 1,且其因数只有 1 和它自身,那么这个数是素数. 例如,2,3,5,7,11 以及 13 是素数. 回顾一下,如果一个数从左往右读与从右往左读是一样的,那么这个数是回文数. 例如,12321 是回文数. 思路: 思路还是挺清晰的,从给入数字向上检索,如果既是回文数,又是素数,就直接输出,如果不满足条件,那么就增加数字,继续判断. 这里有一个小问题,就是所有偶数位的回文…

Find the smallest prime palindrome greater than or equal to N. Recall that a number is prime if it's only divisors are 1 and itself, and it is greater than 1. For example, 2,3,5,7,11 and 13 are primes. Recall that a number is a palindrome if it reads…

嗯... 这道题对于蒟蒻的我来说实在是TQL... 先看一下题:(题目链接:https://www.luogu.org/problemnew/show/P1217) 然后说一下我的做题过程吧: 一看到是普及-的题,就没有考虑什么筛法,只是用最暴力的筛素数的方法做的,然后就导致最后一个点TLE: 接着是一个改进,又用了埃氏筛,可是它太不稳定了,然后数组总是开小,然后就各种TLE,MLE,RE... 最后用的是欧拉筛(线性筛),然后还是最后一个点TLE...然后就很纳闷,看了题解之后才发现有这样的一…

P1217 [USACO1.5]回文质数 Prime Palindromes 题意:给定一个区间,输出其中的回文质数: 学习了洛谷大佬的回溯写法,感觉自己写回溯的能力不是很强: #include <cstdio> #include <iostream> #include <cmath> ; using namespace std; int a[maxn],l,r; bool is_prime(int n) //判断素数 { int x = sqrt(n); ;i<…

Prime Palindromes The number 151 is a prime palindrome because it is both a prime number and a palindrome (it is the same number when read forward as backward). Write a program that finds all prime palindromes in the range of two supplied numbers a a…

Description The number 151 is a prime palindrome because it is both a prime number and a palindrome (it is the same number when read forward as backward). Write a program that finds all prime palindromes in the range of two supplied numbers a and b (…

一.题目描述 The number 151 is a prime palindrome because it is both a prime number and a palindrome (it is the same number when read forward as backward). Write a program that finds all prime palindromes in the range of two supplied numbers a and b (5 <=…