I tried to find all possible longest increasing subsequence using recursion. When I tried an input array {10,22,9,33,21,50,41,40,60,55}
, it worked and the output was:
10 22 33 40 55 /
10 22 33 41 55 /
10 22 33 50 55 /
10 22 33 40 60 /
10 22 33 41 60 /
10 22 33 50 60 /
But when I tried an input array {2,-3,4,90,-2,-1,-10,-9,-8}
, I got an output:
-3 4 90 /
-3 -2 -1 /
-10 -9 -8 /
In this case I didn't get 2 4 90
. What should I change in my code to make it word for this case?
public class Main {
public static void main(String[] args) {
int arr[]={10,22,9,33,21,50,41,40,60,55};
int lis[]=new int[arr.length];
for(int i=0;i<arr.length;i++){
lis[i]=1;
}
for(int i=1;i<arr.length;i++){
for(int j=0;j<i;j++){
if(arr[i]>arr[j]&&lis[i]<lis[j]+1){
lis[i]=lis[j]+1;
}
}
}
int max=0;
for(int i=0;i<arr.length;i++){
if(max<lis[i])
max=lis[i];
}
//**************Recursive Print LIS****************
int rIndex=-1;
for(int i=arr.length-1;i>=0;i--){
if(lis[i]==max){
rIndex=i;
break;
}
}
int res[]=new int[max];
printLISRecursive(arr,rIndex,lis,res,max,max);
}
private static void printLISRecursive(int[] arr, int maxIndex, int[] lis, int[] res, int i, int max) {
if(maxIndex<0)return;
if(max==1&&lis[maxIndex]==1&&i==1){
res[i-1]=arr[maxIndex];
// System.out.println("Using Print Recursion:");
for(int j=0;j<res.length;j++){
System.out.print(res[j]+" ");
}
System.out.println();
return;
}
if(lis[maxIndex]==max){
res[i-1]=arr[maxIndex];
printLISRecursive(arr, maxIndex-1, lis, res, i-1, max-1);
}
printLISRecursive(arr, maxIndex-1, lis, res, i, max);
}
}
public static int lcsrec(String x, String y) {
// If one of the strings has one character, search for that character
// in the other string and return the appropriate answer.
if (x.length() == 1)
return find(x.charAt(0), y);
if (y.length() == 1)
return find(y.charAt(0), x);
// Solve the problem recursively.
// Corresponding beginning characters match.
if (x.charAt(0) == y.charAt(0))
return 1+lcsrec(x.substring(1), y.substring(1));
// Corresponding characters do not match.
else
return max(lcsrec(x,y.substring(1)), lcsrec(x.substring(1),y));
}