2. Write a function sum_square in RISC-V where the function takes an integer n and returns the even- number summation below. If n is not positive, then the function returns 0. sum_square(n) = n + (n-2)+.... +22 n is an even number (n-1) + (n-3) + + 22, n is an odd number For this problem, you need to implement sum_square. The program must be compiled by Venus and use ecall to print your output.