codeforces 616D Longest k-Good Segment

题目链接：【codeforces 616D】

在长度为n的串中找出有k个不同数字的最长连续子串，输出子串开始以及结束的位置

map的简单应用

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <string>
#include <map>
using namespace std;
const int inf=5*1e5+10;
int p[inf];
map<int, int>mp;
int main()
{
	mp.clear();
	int n, k, len=-1, l, r;
	scanf("%d%d", &n, &k);
	for(int i=1; i<=n; i++)
	{
		scanf("%d", &p[i]);
	}
	mp[p[1]]++;
	l=r=1;
	int li=1, ri=1;
	for(int i=2; i<=n; i++)
	{
		mp[p[i]]++;
		int ss = mp.size();
		if(ss==k+1)
		{
			int ans = ri-li+1;
			if(ans>len) 
			{
				len = ans;
				l=li, r=ri;
			}
			while(ss>k)
			{
				mp[p[li]]--;
				if(mp[p[li]]==0) mp.erase(p[li]);
				li++;
				ss = mp.size();
			}
		}
		ri=i;
	}
	int ans = ri-li+1;
	if(ans>len)
	{
		l=li, r=ri;
	}
	printf("%d %d\n", l, r);
	return 0;
}