Use Java - loop etc

Write a program which reads in an unknown amount of input and computes the mean and standard deviation of the input. The formula for standard deviation is given below: s = Squareroot sigma x_i^2 - 1 (sigma x_i)^2 - 1 Input Validation: All numbers must be positive, -1 can be the only negative number used to stop the input. Sample Output 1: Enter positive numbers (-1 to end input): 3.5 8 3.4 2.78 9 10 3.375 -1 Mean: 5.722142857142857 Deviation: 3.1285937431254656