10. Fill in each box in the following equation with “+” or “-”, what is the sum of all different calculation results?
$$
625 \square 125 \square 25 \square 5 \square 1
$$
【Analysis】There are 4 boxes, each box can be filled with + or -, and since these numbers are $5^{4}, 5^{3}, 5^{2}, 5^{1}, 5^{0}$, different +, - fill methods result in different outcomes, so there are $2^{4}=16$ different results.
Among these 16 expressions, the sign before 125 is 8 + and 8 -, the sign before 25 is 8 + and 8 -, the sign before 5 is 8 + and 8 -, and the sign before 1 is 8 + and 8 -.
Thus, in the sum of these 16 expressions, $125, 25, 5, 1$ cancel each other out, and the final result is $625 \times 16=10000$