#
# 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
# 计算两个数之和
# @param s string字符串 表示第一个整数
# @param t string字符串 表示第二个整数
# @return string字符串
#
class Solution:
    def solve(self , s , t ):
        # write code here
        full = 0 #保存进位
        l1,l2 = len(s),len(t)
        length_max = max(l1,l2)
        result = ''
        for i in range(length_max):
            if i<l1:
                x1 = int(s[l1-i-1])
            else:
                x1 = 0
            if i<l2:
                x2 = int(t[l2-i-1])
            else:
                x2 = 0
            tem = x1+x2+full
            if tem >=10: #判断进位
                full =1
                result += (str(tem-10))
            else:
                full = 0 
                result += (str(tem))
        if full == 1: #判断首位是否进位
            result += '1'
        return result[::-1]