The highest bit of sum is t, and we know that the maximum sum of any two one-digit numbers can only exceed ten, so we know that t can only be 1. Then let's consider the unit of addend. If a number plus 1 equals 1, then there can only be 0+ 1 = 1, so we can see that a = 0. T+t on the hundreds can't be full of ten, so the thousands of addends can only be S t+t=v = 65438+. That is, 1+ 1 plus 1 = V of ten digits, so V = 3. s = 8。 That is, a=0, t= 1, v=3 and s=8. That is 8 130+36544.