added another famous dp problem from cses in c++

algorithms/CPlusPlus/Dynamic-Programming/bookshopcses.cpp

@@ -0,0 +1,45 @@
+#include<bits/stdc++.h>
+using namespace std;
+ 
+//bottom_up approach
+ 
+void solve()
+{
+    int n,x;
+    cin>>n>>x;
+    vector<int>(price)(n+1);
+    vector<int>(pages)(n+1);
+   for(int i=1;i<n+1;i++) cin>>price[i];
+   for(int i=1;i<n+1;i++) cin>>pages[i];
+   int dp[n+1][x+1];
+    for(int j=0;j<x+1;j++)
+    {
+        dp[0][j]=0;
+    }
+    for(int i=0;i<n+1;i++)
+    {
+        dp[i][0]=0;
+    }
+   for(int i=1;i<n+1;i++)
+   {
+   for(int j=1;j<x+1;j++)
+   {
+        if(price[i]<=j)
+        {
+            dp[i][j]=max(pages[i]+dp[i-1][j-price[i]],dp[i-1][j]);
+        }
+        else dp[i][j]=dp[i-1][j];
+   }
+    }
+   cout<<dp[n][x];
+}
+int main()
+{
+    int t;
+    t=1;
+    while(t--)
+    {
+        solve();
+        cout<<"\n";
+    }
+}