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n = int(input())
s=[]

def isBadSequence(addStr):
    temp = "".join(s) + addStr
    for i in range(1, len(temp) // 2 + 1):
        if temp[-2 * i : -1 * i] == temp[-1 * i :]:
            return True
        
    return False

def dfs():
    global s
    
    if len(s) == n:
        print("".join(s))
        exit()

    for j in range(1,4):
        if isBadSequence(str(j)):
            continue
            
        s.append(str(j))
        dfs()
        s.pop()
    
dfs()