Slope Calculator

You are given the coordinates of two distinct points in the plane: ( (x_1, y_1) ) and ( (x_2, y_2) ). Your task is to compute the slope ( m ) of the line that connects these two points using the formula: [ m = \frac{y_2 - y_1}{x_2 - x_1} ] If the line is vertical (i.e. when ( x_1 = x_2 )), the slope is undefined and you should output the string undefined.

inputFormat

Input is provided through standard input (stdin) as a single line containing four space-separated numbers: ( x_1, y_1, x_2, y_2 ).

outputFormat

Output to standard output (stdout) the slope of the line. If the slope is defined, print a floating-point number accurate to one decimal place. If the slope is undefined because the line is vertical, print the string undefined.## sample

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