da

Author: kumar80

a.out

@@ -15,10 +15,24 @@ const long long MAX = 1e5 + 10;
 int main()
 {
     fastio;
-    int t = 1; // cin>>t;
+    int t = 1;  cin>>t;
     while (t--)
     {
-      
+      int n ; cin>>n; 
+      int a[n+1]; FOR(i,1,n+1) cin>>a[i];
+      int dp[n+1][n+1];
+      int ans = 0;
+      FOR(i,1,n+1) dp[0][i] = 0,dp[i][0] = 0,dp[1][i] = a[i],ans= max(ans,a[i]);
+      FOR(i,1,n) dp[2][i] = max(a[i],a[i+1]),ans= max(ans,dp[2][i]);
+      FOR(l,3,n+1){
+          FOR(i,1,n+1){
+             int j = i+l-1;
+             if(j>n) continue;
+             dp[l][i] =  max(min(dp[l-2][i+2],dp[l-2][i+1]) + a[i], min(dp[l-2][i], dp[l-2][i+1]) + a[j]); 
+             ans = max(ans,dp[l][i]);
+            }
+      }
+      cout<<ans<<"\n";
     }
 }
 

bca.cpp

@@ -24,17 +24,36 @@ int main()
         FOR(i, 1, n + 1)
             cin >> a[i];
         LL dp[n + 1][2];
-        dp[1][1] = 1;
-        dp[1][0] = a[1] - 1;
-        FOR(i, 2, n + 1)
+        dp[1][1] = a[1];
+        dp[1][0] = 0;
+        dp[2][1] = 0;
+        dp[2][0] = a[1]*a[2] - min(a[1],a[2]);
+        FOR(i, 3, n + 1)
         {
-            dp[i][1] = dp[i-1][0];
+            dp[i][1] = dp[i-1][0] + dp[i-1][1];
             dp[i][0] = dp[i-1][1]*(a[i]-1) + (a[i] <2 ? 0 : dp[i-1][0]*(a[i]-2));
         }
         cout << dp[n][0]+dp[n][1];
     }
 }
-2 3 2
+// 2 3 2
 
-1 3 1
-1 1 3
+// 1 3 1
+// 1 1 3
+
+// 1 2 1
+// 1 3 1
+
+
+// 2 1 2
+// 2 3 2
+
+// 1 2 1
+// 1 3 2 
+// // 2 1 2 
+// // 2 3 2
+
+// 1 2 1
+// 1 3 1
+// // 2 1 2 
+// // 2 3 2

ji.cpp

@@ -0,0 +1,32 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+#define MAXN 100000
+
+int n, t[26][4*MAXN];
+
+void build(int a[], int v, int tl, int tr, int i) {
+    if (tl == tr) {
+        t[i][v] = a[tl];
+    } else {
+        int tm = (tl + tr) / 2;
+        build(a, v*2, tl, tm,i);
+        build(a, v*2+1, tm+1, tr,i);
+        t[i][v] = t[i][v*2] + t[i][v*2+1];
+    }
+}
+
+int sum(int v, int tl, int tr, int l, int r,i) {
+    if (l > r) 
+        return 0;
+    if (l == tl && r == tr) {
+        return t[v];
+    }
+    int tm = (tl + tr) / 2;
+    return sum(v*2, tl, tm, l, min(r, tm))
+           + sum(v*2+1, tm+1, tr, max(l, tm+1), r);
+}
+
+int main(){
+
+}