Update and rename Longest Bitonic subsequence.md to Longest Bitonic subsequence.cpp

Author: stoicfeats

20. Dynamic Programming/Longest Bitonic subsequence.cpp

@@ -0,0 +1,50 @@
+// Question Link : https://practice.geeksforgeeks.org/problems/longest-bitonic-subsequence0824/1# 
+
+
+	class Solution{
+	public:
+	int LongestBitonicSequence(vector<int>arr)
+	{
+	    int n = arr.size();
+	    int dp[n]={0};
+	    
+	    for(int i=0;i<n;i++){
+	        int max =0;
+	        
+	        for(int j=0;j<i;j++){
+	            if(arr[j]<arr[i]){
+	                if(dp[j]>max){
+	                    max = dp[j];
+	                }
+	            }
+	        }
+	        
+	        dp[i] = max +1;
+	    }
+	    
+	    
+	   int lds[n]={0};
+	   for(int i=n-1;i>=0;i--){
+	        int max =0;
+	        
+	        for(int j=n-1;j>i;j--){
+	            if(arr[j]<arr[i]){
+	                if(lds[j]>max){
+	                    max = lds[j];
+	                }
+	            }
+	        }
+	        lds[i] = max +1;
+    }
+	    
+	    int omax=0;
+	    for(int i=0;i<n;i++){
+	        if((dp[i]+lds[i])-1>omax){
+	            omax = (dp[i]+lds[i])-1;
+	        }
+	    }
+	
+	    return omax;
+	}
+};
+