I have 10 numbers (a to j), the sum of them will be equal to a fixed amount X and each number can be used once only. For example:

a+b = X

a+c+e+f = X

c+d+f = X

d+e+f = X

a+d+e+h+j = X

........

There are many combinations and is there a fast way to find all the combinations that is equal to X?

Thank you