CoderForces985F-Isomorphic Strings
3 seconds
256 megabytes
standard input
standard output
You are given a string s of length n consisting of lowercase English letters.
For two given strings s and t, say S is the set of distinct characters of s and T is the set of distinct characters of t. The strings s and t are isomorphic if their lengths are equal and there is a one-to-one mapping (bijection) f between S and T for which f(si) = ti. Formally:
- f(si) = ti for any index i,
- for any character
there is exactly one character
that f(x) = y,
- for any character
there is exactly one character
that f(x) = y.
For example, the strings "aababc" and "bbcbcz" are isomorphic. Also the strings "aaaww" and "wwwaa" are isomorphic. The following pairs of strings are not isomorphic: "aab" and "bbb", "test" and "best".
You have to handle m queries characterized by three integers x, y, len (1 ≤ x, y ≤ n - len + 1). For each query check if two substrings s[x... x + len - 1] and s[y... y + len - 1] are isomorphic.
The first line contains two space-separated integers n and m (1 ≤ n ≤ 2·105, 1 ≤ m ≤ 2·105) — the length of the string s and the number of queries.
The second line contains string s consisting of n lowercase English letters.
The following m lines contain a single query on each line: xi, yi and leni (1 ≤ xi, yi ≤ n, 1 ≤ leni ≤ n - max(xi, yi) + 1) — the description of the pair of the substrings to check.
For each query in a separate line print "YES" if substrings s[xi... xi + leni - 1] and s[yi... yi + leni - 1] are isomorphic and "NO" otherwise.
7 4
abacaba
1 1 1
1 4 2
2 1 3
2 4 3
YES
YES
NO
YES
The queries in the example are following:
- substrings "a" and "a" are isomorphic: f(a) = a;
- substrings "ab" and "ca" are isomorphic: f(a) = c, f(b) = a;
- substrings "bac" and "aba" are not isomorphic since f(b) and f(c) must be equal to a at same time;
- substrings "bac" and "cab" are isomorphic: f(b) = c, f(a) = a, f(c) = b.
题意:在一个字符串里随意找两个长度相同的子串,比较是否为同构字符串;
字符串hash,比较两个字符串的每个字符的hash值是否相同;
AC;
#include<iostream>
#include<queue>
#include<cstdio>
#include<vector>
#include<algorithm>
using namespace std;
typedef long long ll;
const int maxn=2e5+10;
const ll MOD=1e9+7;
ll h[26][maxn],x=107,px[maxn];
char s[maxn];
int main()
{
int n,m;
scanf("%d%d", &n,&m);
scanf("%s", s+1);
px[0]=1;
for(int i = 1; i <= n; ++i) px[i]=px[i-1]*x%MOD;
for(int i = 0; i < 26; ++i)
{
for(int j = 1; j <= n; ++j) h[i][j]=(h[i][j-1]*x+int(s[j] == (i+'a')))%MOD;
}
while(m--)
{
int x,y,l;
scanf("%d%d%d", &x,&y,&l);
vector<int> p,q;
for(int i = 0; i < 26; ++i)
{
p.push_back(((h[i][x+l-1]-px[l]*h[i][x-1]%MOD)%MOD+MOD)%MOD);
q.push_back(((h[i][y+l-1]-px[l]*h[i][y-1]%MOD)%MOD+MOD)%MOD);
}
sort(q.begin(),q.end());sort(p.begin(),p.end());
printf("%s\n", p==q? "YES":"NO");
}
return 0;
}
字符串
CoderForces985F-Isomorphic Strings的更多相关文章
- [LeetCode] Isomorphic Strings
Isomorphic Strings Total Accepted: 30898 Total Submissions: 120944 Difficulty: Easy Given two string ...
- leetcode:Isomorphic Strings
Isomorphic Strings Given two strings s and t, determine if they are isomorphic. Two strings are isom ...
- Codeforces Educational Codeforces Round 44 (Rated for Div. 2) F. Isomorphic Strings
Codeforces Educational Codeforces Round 44 (Rated for Div. 2) F. Isomorphic Strings 题目连接: http://cod ...
- [leetcode]205. Isomorphic Strings 同构字符串
Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the chara ...
- Codeforces 985 F - Isomorphic Strings
F - Isomorphic Strings 思路:字符串hash 对于每一个字母单独hash 对于一段区间,求出每个字母的hash值,然后排序,如果能匹配上,就说明在这段区间存在字母间的一一映射 代 ...
- Educational Codeforces Round 44 (Rated for Div. 2) F - Isomorphic Strings
F - Isomorphic Strings 题目大意:给你一个长度为n 由小写字母组成的字符串,有m个询问, 每个询问给你两个区间, 问你xi,yi能不能形成映射关系. 思路:这个题意好难懂啊... ...
- CodeForces985F -- Isomorphic Strings
F. Isomorphic Strings time limit per test 3 seconds memory limit per test 256 megabytes input standa ...
- LeetCode 205. 同构字符串(Isomorphic Strings)
205. 同构字符串 205. Isomorphic Strings
- LeetCode_205. Isomorphic Strings
205. Isomorphic Strings Easy Given two strings s and t, determine if they are isomorphic. Two string ...
- 【刷题-LeetCode】205. Isomorphic Strings
Isomorphic Strings Given two strings *s* and *t*, determine if they are isomorphic. Two strings are ...
随机推荐
- 有关html的标签以及css属性(border、div)
border 边框css属性 边框颜色 border-color边框样式 border-style:solid (实线)dashed(虚线)默认为none边框粗细 border-width:1px:默 ...
- 破解加密Excel
打开要解除保护的EXCEL ALT+F11----插入模块----复制粘贴代码----F5============================代码========================= ...
- 微擎使用post提交,并显示弹出层
微擎使用post提交,并显示弹出层 function changeStatus(id, status) { // 提交数据 var id = parseInt(id); var status = pa ...
- nyoj 29-求转置矩阵问题 (行,列位置调换)
29-求转置矩阵问题 内存限制:64MB 时间限制:3000ms Special Judge: No accepted:8 submit:18 题目描述: 求一个三行三列的转置矩阵. 输入描述: 第一 ...
- nodejs入门之模块
nodejs模块语法与开闭原则 nodejs模块的底层实现 一.nodejs模块语法与开闭原则 关于nodejs模块我在之前的两篇博客中都有涉及,但都没有对nodejs模块的底层做做任何探讨,但是为了 ...
- gdb(ddd,kdevelop等)调试ZeroIce开发的应用程序,中断信号引起的问题
不作文,只记要点. 1.Ice::Application的程序框架默认对SIGHUP, SIGINT, SIGTERM进行处理.目的就是捕捉Ctrl+C发出信号有序地结束程序.这个功能扰乱了我们使用g ...
- opencv 6 图像轮廓与图像分割修复 2 使用多边形将轮廓包围
使用多边形将轮廓包围 返回外部矩阵边界(boundingRect()函数) 寻找最小包围矩形(minAreaRect()函数) 寻找最小包围圆形(minEnclosingCircle函数) 用椭圆拟合 ...
- JS三座大山再学习(二、作用域和闭包)
原文地址 作用域 JS中有两种作用域:全局作用域|局部作用域 栗子1 console.log(name); //undefined var name = '波妞'; var like = '宗介' c ...
- ubuntu server 1604 设置笔记本盒盖 不操作
sudo vim /etc/systemd/logind.conf //打开配置文件 找到 #HandleLidSwitch=suspend 改为 HandleLidSwitch=ignore ...
- 扛把子组20191114-4 Beta发布用户使用报告
此作业的要求参见:http://edu.cnblogs.com/campus/nenu/2019fall/homework/10007 小组情况: 队名:扛把子 组长:孙晓宇 组员:宋晓丽 梁梦瑶 韩 ...