Python3 代码

def dfs (u, num, st):
    global n

    if u > n :
        for i in range (1, n+1):
            print (num[i], end = " ")
        print("")
    else:
        for i in range (1, n+1):
            # print (u, i, st[i])
            if st[i] == False:
                st[i] = True;
                num[u] = i
                dfs (u + 1, num, st)
                st [i] = False

n = int (input())
num = [0]*(n+1)
st = [False]*(n+1)
dfs (1, num, st)