Added Longest Repeated Subsequence DP Problem

Author: shikharp16

DP/Longest Repeated Subsequence/LonRep.cpp

@@ -0,0 +1,70 @@
+
+// C++ program to find the longest repeated 
+// subsequence 
+#include <bits/stdc++.h> 
+using namespace std; 
+  
+// This function mainly returns LCS(str, str) 
+// with a condition that same characters at 
+// same index are not considered. 
+string longestRepeatedSubSeq(string str) 
+{ 
+    // THIS PART OF CODE IS SAME AS BELOW POST.  
+    // IT FILLS dp[][] 
+    // https://www.geeksforgeeks.org/longest-repeating-subsequence/ 
+    // OR the code mentioned above. 
+    int n = str.length(); 
+    int dp[n+1][n+1]; 
+    for (int i=0; i<=n; i++) 
+        for (int j=0; j<=n; j++) 
+            dp[i][j] = 0; 
+    for (int i=1; i<=n; i++) 
+        for (int j=1; j<=n; j++) 
+            if (str[i-1] == str[j-1] && i != j) 
+                dp[i][j] =  1 + dp[i-1][j-1]; 
+            else
+                dp[i][j] = max(dp[i][j-1], dp[i-1][j]); 
+  
+  
+    // THIS PART OF CODE FINDS THE RESULT STRING USING DP[][] 
+    // Initialize result 
+    string res = ""; 
+  
+    // Traverse dp[][] from bottom right 
+    int i = n, j = n; 
+    while (i > 0 && j > 0) 
+    { 
+        // If this cell is same as diagonally 
+        // adjacent cell just above it, then  
+        // same characters are present at  
+        // str[i-1] and str[j-1]. Append any  
+        // of them to result. 
+        if (dp[i][j] == dp[i-1][j-1] + 1) 
+        { 
+           res = res + str[i-1]; 
+           i--; 
+           j--; 
+        } 
+  
+        // Otherwise we move to the side 
+        // that that gave us maximum result 
+        else if (dp[i][j] == dp[i-1][j]) 
+            i--; 
+        else
+            j--; 
+    } 
+  
+    // Since we traverse dp[][] from bottom, 
+    // we get result in reverse order. 
+    reverse(res.begin(), res.end()); 
+  
+    return res; 
+} 
+  
+// Driver Program 
+int main() 
+{ 
+    string str = "AABEBCDD"; 
+    cout << longestRepeatedSubSeq(str); 
+    return 0; 
+}