Merge pull request matthewsamuel95#82 from aniket7joshi/aniket7joshi_LCIS_CPP

Issue matthewsamuel95#81 lcis resolved

Author: matthewsamuel95

DP/LCIS/lcis.cpp

@@ -0,0 +1,96 @@
+#include<bits/stdc++.h>
+using namespace std;
+ 
+// Returns the length and the LCIS of two
+// arrays arr1[0..n-1] and arr2[0..m-1] and
+// prints LCIS
+int LCIS(int arr1[], int n, int arr2[], int m)
+{
+    // table[j] is going to store length of LCIS
+    // ending with arr2[j]. We initialize it as 0,
+    int table[m], parent[m];
+    for (int j=0; j<m; j++)
+        table[j] = 0;
+ 
+    // Traverse all elements of arr1[]
+    for (int i=0; i<n; i++)
+    {
+        // Initialize current length of LCIS
+        int current = 0, last = -1;
+ 
+        // For each element of arr1[], trvarse all
+        // elements of arr2[].
+        for (int j=0; j<m; j++)
+        {
+            // If both the array have same elements.
+            // Note that we don't break the loop here.
+            if (arr1[i] == arr2[j])
+            {
+                if (current + 1 > table[j])
+                {
+                    table[j] = current + 1;
+                    parent[j] = last;
+                }
+            }
+ 
+            /* Now seek for previous smaller common
+               element for current element of arr1 */
+            if (arr1[i] > arr2[j])
+            {
+                if (table[j] > current)
+                {
+                    current = table[j];
+                    last = j;
+                }
+            }
+        }
+    }
+ 
+    // The maximum value in table[] is out result
+    int result = 0, index = -1;
+    for (int i=0; i<m; i++)
+    {
+        if (table[i] > result)
+        {
+           result = table[i];
+           index = i;
+        }
+    }
+ 
+    // LCIS is going to store elements of LCIS
+    int lcis[result];
+    for (int i=0; index != -1; i++)
+    {
+        lcis[i] = arr2[index];
+        index = parent[index];
+    }
+ 
+    cout << "The LCIS is : ";
+    for (int i=result-1; i>=0; i--)
+        printf ("%d ", lcis[i]);
+ 
+    return result;
+}
+ 
+/* Driver program to test above function */
+int main()
+{
+    int arr1[1000];
+    int arr2[1000];
+    int n,m;
+    printf("Enter size of 2 arrays");
+    scanf("%d%d",&n,&m);
+    printf("Enter 1st array\n");
+    for(int i = 0;i<n;i++)
+    {
+        scanf("%d",&arr1[i]);
+    }
+    printf("Enter 2nd array\n");
+    for(int i = 0;i<m;i++)
+    {
+        scanf("%d",&arr2[i]);
+    }
+    cout << "\nLength of LCIS is "
+         << LCIS(arr1, n, arr2, m);
+    return (0);
+}