【双指针】Acwing799.最长连续不重复子序列

Acwing799.最长连续不重复子序列

题解

#include <iostream>
#include <cstdio>

using namespace std;

const int N = 1e5+10;

int a[N], s[N];

int main()
{
    int n;
    scanf("%d",&n);
    for(int i = 0; i < n; ++i)
        scanf("%d",&a[i]);
    int ans = 0;
    for(int i = 0, j = 0; i < n; ++i)
    {
        s[a[i]]++;
        while(i > j && s[a[i]] > 1) s[a[j ++ ]] --;
        ans = max(ans, i - j + 1);
    }
    printf("%d\n",ans);
    return 0;
}