update

src/20241118/T541155.cpp

@@ -3,45 +3,30 @@
 #include <iostream>
 #include <set>
 
-using ll=int64_t;
+using ll = int64_t;
 using std::cin, std::cout;
 
-const ll maxn=1e5+5;
+const ll maxn = 1e5+5;
-ll t, n, a[maxn], inf=(1l<<(sizeof(inf)*8-5)), ninf=-inf;
+ll t, n, a[maxn], ans, inf=(1l<<(sizeof(inf)*8-4));
 
 int main(){
     std::iostream::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
 
     cin>>t;
     while(t--){
-        std::multiset<ll> rset, lset;
+        ans = -inf;
         cin>>n;
+        std::multiset<ll> lset, rset;
         for(ll i{1};i<=n;i++){
             cin>>a[i];
             rset.emplace(a[i]);
         }
         rset.erase(rset.find(a[1]));
         lset.emplace(a[1]);
-        ll ans{ninf};
+        for(ll i{2};i<n;i++){
-        for(ll j{2};j<n;j++){
+            
-            rset.erase(rset.find(a[j]));
+            lset.emplace(a[i]);
-            auto lit {lset.lower_bound(a[j])};
-            decltype(rset.end()) rit;
-            if(lit==lset.end())lit--;
-            while(*lit>=a[j]){
-                if(lit==lset.begin())goto end;
-                --lit;
-            }
-            if(lit==lset.end() || (*lit)>=a[j])goto end;
-            rit = rset.end();
-            --rit;
-            if(*rit<=a[j])goto end;
-            ans=std::max(ans, (*lit) * a[j] * (*rit));
-
-            end:;
-            lset.emplace(a[j]);
         }
-        cout<<(ans==ninf?-1:ans)<<'\n';
+        cout<<(ans==-inf?-1:ans)<<'\n';
-        // cout<<ans<<'\n';
     }
 }

src/20241118/T541155_in.cpp

@@ -0,0 +1,18 @@
+#include <cstdint>
+#include <iostream>
+#include <random>
+
+using ll = int64_t;
+using std::cin, std::cout;
+
+const ll inf = (1l<<32);
+
+int main(){
+    std::random_device rd;
+    std::mt19937_64 mt{rd()};
+    std::uniform_int_distribution<ll> uid{-inf, inf};
+    ll t {100};
+    while (t--) {
+        cout<<uid(mt)<<'\n';
+    }
+}

src/20241118/T541155_pai.cpp

@@ -0,0 +1,28 @@
+#include <algorithm>
+#include <cstdint>
+#include <iostream>
+
+using ll = int64_t;
+using std::cin, std::cout;
+
+const ll maxn = 1e5+5;
+ll t, n, a[maxn], ans, inf=(1l<<(sizeof(inf)*8-4));
+
+int main(){
+    std::iostream::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
+
+    cin>>t;
+    while(t--){
+        ans = -inf;
+        cin>>n;
+        for(ll i{1};i<=n;i++)cin>>a[i];
+        for(ll i{1};i<n-1;i++)
+            for(ll j{i+1};j<n;j++)
+                for(ll k{j+1};k<=n;k++){
+                    if(a[i]<a[j] && a[j]<a[k]){
+                        ans=std::max(ans, a[i]*a[j]*a[k]);
+                    }
+                }
+        cout<<(ans==-inf?-1:ans)<<'\n';
+    }
+}