delete pics to save space

2.11572.cpp

@@ -0,0 +1,29 @@
+#include<cstdio>
+#include<set>
+#include<algorithm>
+using namespace std;
+
+const int maxn=1000000+5;
+int A[maxn]; 
+
+int main()
+{
+    int t,n;
+    scanf("%d",&t);
+    while(t--)
+    {
+        scanf("%d",&n);
+        for(int i=0;i<n;i++) scanf("%d",A+i);
+        
+        set<int> s;
+        int L=0,R=0,ans=0;
+        while(R<n)
+        {
+            while(R<n&&!s.count(A[R])) s.insert(A[R++]);
+            ans=max(ans,R-L);
+            s.erase(A[L++]);
+        }
+        printf("%d\n",ans);
+    }
+    return 0;
+}