Create 1027. Longest Arithmetic Subsequence.cpp

Author: Yashmenaria1

1027. Longest Arithmetic Subsequence.cpp

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+class Solution {
+public:
+    int dp[1001][1001];
+    int longestArithSeqLength(vector<int>& nums) {
+        memset(dp , 0 , sizeof(dp));
+         int n=nums.size();
+         int maxlen =1;
+         for(int i=1 ; i<n ;i++)
+         {
+             for(int j=0;j<i;j++)
+             {
+                 int diff=nums[i]-nums[j] + 500;
+                 
+                 dp[i][diff] = max(dp[i][diff] , 1 + dp[j][diff]);
+                 
+                 maxlen = max(maxlen , dp[i][diff]);
+                 
+             }
+         }
+         
+         return maxlen + 1;
+    }
+
+};