Uva11572-Unique Snowflakes(滑动窗口)

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define CLR(x , v)        memset(x , v , sizeof(x))
 4 static const int MAXN = 1e6 + 10;
 5 int t , n;
 6 int data[MAXN];
 7 set<int> s;
 8 int ans = 0;
 9 int main()
10 {
11     scanf("%d" , &t);
12     while(t--)
13     {
14         CLR(data , 0);
15         s.clear();
16         ans = 0;
17         scanf("%d" , &n);
18         for(int i = 1 ; i <= n ; ++i)
19             scanf("%d" , data + i);
20         int l = 1 , r = 1;
21         while(r <= n)
22         {
23             while(r <= n && !s.count(data[r]))
24                 s.insert(data[r++]);
25             int si = s.size();
26             ans = max(ans , si);
27             s.erase(data[l++]);
28         }
29         printf("%d\n" , ans);
30     }
31 }