如何在不使用任何数组的情况下找到浮点数列表中的最小数字？

I would like to find the smallest number in a list of floats from the file that the user types in without using any arrays, but I can't seem to figure out how to do it. This is what I have currently but it doesn't work at all. Any help would be appreciated and please feel free to edit for phrasing.I would like to find the smallest number in a l