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Greedy beats DP this time...

I tried several DP solutions first, but all failed with RETLE. If you 'feel' the problem, Greedy should be working:

(A solution from discussion)

def getPivot(n):
    while n > 0:
        if n % 3 == 0:
            break;
        else:
            n -= 5
    return n
        
T = input()
for i in xrange(T):
    N = int(input())
    pivot = getPivot(N)
    if pivot < 0:
        print -1
    else:
        str = ''
        repeat = pivot / 3
        while repeat > 0:
            str += '555'
            repeat -= 1
        repeat = (N - pivot) / 5
        while repeat > 0:
            str += '33333'
            repeat -= 1
        print str