First of all, the middle two lines of the equation are odd, which can only be odd+even, so the addition of the middle two lines needs to occupy two odd numbers and two even numbers;

The first subtraction, the subtraction of two numbers is 1, which can only be odd and even;

In the subtraction of the fourth line, two numbers MINUS two can only be two odd numbers or two even numbers; But please note that the first three equations have occupied three odd numbers and three even numbers, and only one odd number and one even number are left in the fourth line, so these four equations cannot be established at the same time!

I hope I can make you understand that don't try to do this problem again. There must be no solution.