Improve the program of Exercise •• E7.19 to work correctly when the data set contains negative values.

Data from Exercise E 7.19

Write a program that reads a sequence of input values and displays a bar chart of the values, using asterisks, like this:
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You may assume that all values are positive. First figure out the maximum value.
That value’s bar should be drawn with 40 asterisks. Shorter bars should use proportionally fewer asterisks.