def merge_sort(arr):
    mergeSort(arr, 0, len(arr)-1)
    return arr

def merge(arr, l, m, r):
    if(arr[m] > arr[m+1]):
        #Left Buffer
        L = arr[l:m+1]

        #Right Buffer
        R = arr[m+1:r+1]

        # Merge the temp arrays back into arr[l..r]

        i = 0     # Initial index of first subarray
        j = 0     # Initial index of second subarray
        k = l     # Initial index of merged subarray

        #Length of both the buffers
        len_l  = m+1-l
        len_r = r-m

        #Merging of two sorted subarrays
        while i < len_l and j < len_r:
            if L[i] <= R[j]:
                arr[k] = L[i]
                i += 1
            else:
                arr[k] = R[j]
                j += 1
            k += 1

        #Copy if there are any elements in the left subarray
        #Note that the right subarray is already there and hence does not need to be copied
        while(i < len_l):
            arr[k] = L[i]
            i += 1
            k += 1

def mergeSort(arr,l, r):
    if l < r:

        m = (l+r)//2

        # Sort first and second subarray
        mergeSort(arr, l, m)
        mergeSort(arr, m+1, r)

        #Merge both the subarrays
        merge(arr, l, m, r)

if __name__ == '__main__':

    t = int(input())
    arr = []
    try:
        for t_itr in range(t):
            n = input()
            arr.append(n)

        arr = list(map(int, arr))

        result = merge_sort(arr)
    except:
        arr = list(map(int, n.rstrip().split()))

        result = merge_sort(arr)

    print(str(result).replace(" ", ""))