Day 50 B. Ternary String

该博客主要介绍了如何解决一个计算机科学问题:在给定的字符串中找到最短的连续子串,这个子串必须至少包含1、2和3这三个数字。博主提供了一个C++代码实现,使用双指针方法来寻找符合条件的子串,并给出了样例输入和输出。文章强调了在字符串处理和算法设计上的技巧和思路。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

Problem
You are given a string s such that each its character is either 1, 2, or 3. You have to choose the shortest contiguous substring of s such that it contains each of these three characters at least once.

A contiguous substring of string s is a string that can be obtained from s by removing some (possibly zero) characters from the beginning of s and some (possibly zero) characters from the end of s.

Input
The first line contains one integer t (1≤t≤20000) — the number of test cases.

Each test case consists of one line containing the string s (1≤|s|≤200000). It is guaranteed that each character of s is either 1, 2, or 3.

The sum of lengths of all strings in all test cases does not exceed 200000.

Output
For each test case, print one integer — the length of the shortest contiguous substring of s containing all three types of characters at least once. If there is no such substring, print 0 instead.

Example
input
7
123
12222133333332
112233
332211
12121212
333333
31121
output
3
3
4
4
0
0
4

Note
Consider the example test:

In the first test case, the substring 123 can be used.

In the second test case, the substring 213 can be used.

In the third test case, the substring 1223 can be used.

In the fourth test case, the substring 3221 can be used.

In the fifth test case, there is no character 3 in s.

In the sixth test case, there is no character 1 in s.

In the seventh test case, the substring 3112 can be used.

#include<iostream>
#include<algorithm>
#include<string.h>
#include<vector>
#include<stdio.h>
#include<limits.h>
#include<queue>
#include<cmath>
#include<set>
#include<map>
using namespace std;
const int INF = 0x3f3f3f3f;
//题目求最短子串长度 其中子串里需含有123三个数字 双指针
int main()
{
	int t;
	cin >> t;
	string str;
	for (int i = 0; i < t; i++)
	{
		cin >> str;
		int left = 0;
		int res = INF;
		int num[4] = { 0 };
		for (int j = 0; j < str.length(); j++)
		{
			num[str[j] - '0']++;
			while (num[str[left] - '0'] >= 2)
			{
				num[str[left] - '0']--;
				left++;
			}
			if (num[1] && num[2] && num[3])
			{
				res = min(res, j - left + 1);
			}
		}
		if (res == INF)
		{
			cout << 0 << endl;
		}
		else
		{
			cout << res << endl;
		}
	}
	return 0;
}
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值