Error in implementation of merge sort in java?

Question

I made the following code in java for merge sort but in the output I'm getting output: -
0 0 0 0 0 0
I have tried debugging it for the past two hours. Where am I going wrong here?

public class MergeSort {

    public static void Mergesort(int[] a){
        int n=a.length;
        if(n<2)
            return;
        int mid=n/2;
        int[] left=new int[mid];
        int[] right=new int[n-mid];
        for(int i=0;i<mid-1;i++)
            {left[i]=a[i];}
        for(int i=mid;i<n-1;i++)
            {right[i-mid]=a[i];}
        Mergesort(left);
        Mergesort(right);
        merge(left,right,a);
    }

    public static void merge(int[]x,int[] y,int[] z){
        int p=x.length;
        int q=y.length;
        int i=0;int j=0;int k=0;
        while(i<p&&j<q){
            if(x[i]<=y[j])
                z[k++]=x[i++];

            else
                z[k++]=y[j++];
        }
        while(i<p) z[k++]=x[i++];
        while(j<q) z[k++]=y[j++];


    }



    public static void main(String[] args) {

        int[] arr={9,10,8,5,1,0};
        Mergesort(arr);
        for(int l=0;l<arr.length;l++)
        {System.out.println(arr[l]);}


    }

}

Output is 0 0 0 0 0 0
I think there is something wrong with the partitioning !

Answer 1

Using the debugger I can see that

for(int i=0;i<mid-1;i++)

and

for(int i=mid;i<n-1;i++)

should be

for(int i = 0; i < mid; i++)

and

for(int i = mid; i < n; i++)

Your code doesn't copy the last element and eventually you just have all 0's