D进制的A+B

def solve(a, b, d):
    a = int(a)
    b = int(b)
    d = int(d)
    total = a + b
    if total == 0:
        print('0')
        return
    result = []
    while total > 0:
        result.append(str(total % d))
        total //= d
    print(''.join(result[::-1]))