Problem: A positive integer X is said to be a lunlun number if and only if the following condition is satisfied:    * In the base ten representation of X (without leading zeros), for every pair of two adjacent digits, the absolute difference of those digits is at most 1.  For example, 1234, 1, and 334 are lunlun numbers, while none of 31415, 119, or 13579 is.  You are given a positive integer K. Find the K-th smallest lunlun number.

Submission attempts (in order):
n = int(input())
D = []

def FindOtvet(i, j, otv):
    if i == 0:
        return ''
    if j == 0:
        if (otv + D[i - 1][j]) < n:
            otv += D[i - 1][j]
            return str(j + 1) + FindOtvet(i - 1, j + 1, otv)
        else:
            return str(j) + FindOtvet(i - 1, j, otv)
    elif j == 9:
        if (otv + D[i - 1][j - 1]) < n:
            otv += D[i - 1][j - 1]
            return str(j) + FindOtvet(i - 1, j, otv)
        else:
            return str(j - 1) + FindOtvet(i - 1, j - 1, otv)
    else:
        if (otv + D[i - 1][j - 1]) < n:
            otv += D[i - 1][j - 1]
            if (otv + D[i - 1][j]) < n:
                otv += D[i - 1][j]
                return str(j + 1) + FindOtvet(i - 1, j + 1, otv)
            else:
                return str(j) + FindOtvet(i - 1, j, otv)
        else:
            return str(j - 1) + FindOtvet(i - 1, j - 1, otv)

arr = []
for i in range(10):
    arr.append(1)
D.append(arr)
totalSum = 9
i = 1
respI = 0
respJ = 0
while respI == 0 and respJ == 0:
    arr = []
    for j in range(10):
        if j == 0:
            arr.append(D[i - 1][j] + D[i - 1][j + 1])
        elif j < 9:
            arr.append(D[i - 1][j - 1] + D[i - 1][j] + D[i - 1][j + 1])
        else:
            arr.append(D[i - 1][j - 1] + D[i - 1][j])
        if j > 0:
            if (totalSum + arr[j]) >= n:
                respI = i
                respJ = j
                break
            totalSum += arr[j]
    D.append(arr)
    i += 1
print(*D)
respStr = str(respJ)
print(respStr + FindOtvet(respI, respJ, totalSum))


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

def FindOtvet(i, j, otv):
    if i == 0:
        return ''
    if j == 0:
        if (otv + D[i - 1][j]) < n:
            otv += D[i - 1][j]
            return str(j + 1) + FindOtvet(i - 1, j + 1, otv)
        else:
            return str(j) + FindOtvet(i - 1, j, otv)
    elif j == 9:
        if (otv + D[i - 1][j - 1]) < n:
            otv += D[i - 1][j - 1]
            return str(j) + FindOtvet(i - 1, j, otv)
        else:
            return str(j - 1) + FindOtvet(i - 1, j - 1, otv)
    else:
        if (otv + D[i - 1][j - 1]) < n:
            otv += D[i - 1][j - 1]
            if (otv + D[i - 1][j]) < n:
                otv += D[i - 1][j]
                return str(j + 1) + FindOtvet(i - 1, j + 1, otv)
            else:
                return str(j) + FindOtvet(i - 1, j, otv)
        else:
            return str(j - 1) + FindOtvet(i - 1, j - 1, otv)

arr = []
if n < 10:
    print(n)
    exit()
for i in range(10):
    arr.append(1)
D.append(arr)
totalSum = 9
i = 1
respI = 0
respJ = 0
while respI == 0 and respJ == 0:
    arr = []
    for j in range(10):
        if j == 0:
            arr.append(D[i - 1][j] + D[i - 1][j + 1])
        elif j < 9:
            arr.append(D[i - 1][j - 1] + D[i - 1][j] + D[i - 1][j + 1])
        else:
            arr.append(D[i - 1][j - 1] + D[i - 1][j])
        if j > 0:
            if (totalSum + arr[j]) >= n:
                respI = i
                respJ = j
                break
            totalSum += arr[j]
    D.append(arr)
    i += 1
respStr = str(respJ)
print(respStr + FindOtvet(respI, respJ, totalSum))


Verdicts: Wrong Answer

Accepted