def merge(arr,l,m,r): n1 = m-l+1 n2 = r-m L=[0]*(n1) R=[0]*(n2) for i in range(0,n1): L[i] = arr[l+i] for j in range(0,n2): R[j] = arr[m+1+j] i = 0 j = 0 k = 1 while i