Envío 4767

Código

def add(s, t):
    res, c = [], 0
    i, j = len(s) - 1, len(t) - 1
    while i >= 0 or j >= 0 or c:
        ds = int(s[i]) if i >= 0 else 0
        dt = int(t[j]) if j >= 0 else 0
        c, nd = divmod(ds + dt + c, 10)
        res.append(str(nd))
        i, j = i - 1, j - 1
    return "".join(reversed(res))

if __name__ == "__main__":
    s = input()
    t = input()
    print(add(s, t))