A palindrome is a word, number, or phrase that reads the same forwards as backwards. For example,the name “anna” is a palindrome. Numbers can also be palindromes (e.g. 151 or 753357). Additionallynumbers can of course be ordered in size. The first few…

 J - Palindrome Numbers Time Limit:3000MS     Memory Limit:0KB     64bit IO Format:%lld & %llu Submit Status Practice UVALive 2889       WA了一版面,我也是醉了,就由于一个编译环境不同.. ....   说多了都是泪.   题目链接:请点击id=33603" target="_blank" style="padding…

题目链接:uva 12050 - Palindrome Numbers 题意:求第n个回文串 思路:首先可以知道的是长度为k的回文串个数有9*10^(k-1),那么依次计算,得出n是长度为多少的串,然后就得到是长度为多少的第几个的回文串了,有个细节注意的是, n计算完后要-1! 下面给出AC代码: #include <bits/stdc++.h> typedef long long ll; using namespace std; ; ll num[maxn]; int n,ans[maxn]…

题目链接:https://vjudge.net/contest/237394#problem/E A palindrome is a word, number, or phrase that reads the same forwards as backwards. For example, the name “anna” is a palindrome. Numbers can also be palindromes (e.g. 151 or 753357). Additionally num…

A palindrome is a word, number, or phrase that reads the same forwards as backwards. For example, the name “anna” is a palindrome. Numbers can also be palindromes (e.g. 151 or 753357). Additionally numbers can of course be ordered in size. The first…

Determine whether an integer is a palindrome. Do this without extra space. 尝试用两头分别比较的方法,结果发现无法解决1000021这种问题 public class Solution { public boolean isPalindrome(int x) { if(x<0) return false; int lastbit=x%10; int firstbit; int num=x; int bits=0; whil…

题目链接 水题,LA我居然没找到在那里. #include <cstdio> #include <cstring> #include <string> #include <cmath> #include <ctime> #include <cstdlib> #include <iostream> using namespace std; #define LL long long LL dp[],bin[]; ],s; vo…

题目大意:给出i,输出第i个镜像数,不能有前导0. 题解:从外层开始模拟 #include <stdio.h> int p(int x) { int sum, i; ;i<=x;i++) sum *= ; return sum; } int main() { ], c; while(~scanf("%d", &n)) { ) break; i=; *p((i-)/)) { n -= *p((i-)/); i++; } c = (i+)/; t=; while(…

输出第n个回文数. 规律就是一位和两位的回文数各有9个,三位四位的回文数各有90个,以此类推. 给出n,可以先判定一下第n个回文数的位数,然后后面也不难推,但是有很多细节需要注意. #include <cstdio> #include <algorithm> #include <cassert> using namespace std; typedef long long LL; ; LL a[maxl + ], sum[maxl + ], pow10[maxl]; i…

题目链接: http://poj.org/problem?id=2402 题目大意就是让你找到第n个回文数是什么. 第一个思路当然是一个一个地构造回文数直到找到第n个回文数为止(也许大部分人一开始都是这样的思路). 很明显找到第n个之前的所有操作都是浪费, 这也是这个方法的最大弱点. 抱着侥幸心理(谁知道数据弱不弱啊)用这种方法提交了下, TLE (在另一个OJ上提交是9个测试点过了6个). 第二个思路也很容易想到, 但是比第一个思路要麻烦: 第n个回文数的每位数字都与n有一定的关联. 也就是说…