Longest increasing subsequence doubt

#1

my code is giving wrong answer for lis-top down approach please help code:
#include
using namespace std;
int lis(int *arr,int i,in
t j,int n)
{
if( arr[j] <arr[i] || j==n)
{
return 0;
}

int inc=1+lis(arr,i,j+1,n);
int ex=lis(arr,i,j+1,n);
int x=max(inc,ex);
return x;

}
int main()
{
int n;
cin>>n;
int a[1000];
for(int i=0;i<n;i++)
{
cin>>a[i];
}
cout<<lis(a,0,0,n);
}

#2

@khushi91200 hey this logic will not work here as you have to check previous all eleements of current element as is is increasing subsequence.Here is pseudo code for that:
public int LIS(int[] arr) {
return LISLength(arr, Integer.MIN_VALUE, 0);
}

public int LISLength(int[] arr, int prev, int current) {
    if (current == arr.length) {
        return 0;
    }
    int include = 0;
    if (arr[current] > prev) {
        include = 1 + LISLength(arr, arr[current], current + 1);
    }
    int exclude = LISLength(arr, prev, current + 1);
    return Math.max(include, exclude);
}
#3

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