N = int(input())
match = {1: 0, 2: 1, 5: 5, 4: 4, 3: 7, 7: 8, 6: 9}
res = 0
i = 1
while N > 0:
    res *= i
    if N >= 5:
        res += 7
        N -= 3
    elif N >= 4:
        res += 1
        N -= 2
    else:
        res += match[N]
        N -= N
    i *= 10
print(res)