design and solve in java a simple DC circuits composed of any number of resistors and voltage sourced. Classes, interfaces, methods are up to the designer to decide what they need. The one exception is that you must have class called UserMain that has a main$()$ method that reads and interprets input from stdin $($by default, the keyboard$).$ The format for describing $($for example$)$ a $5\mathrm{.}2$ Ohm resistor connected between nodes $2$ and $3$ is: r $235\mathrm{.}2$ A complete circuit could be described as follows: v $102\mathrm{.}0$

r $120\mathrm{.}25$

v $203$

r $230\mathrm{.}5$

r $301\mathrm{.}0$

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In addition to lines describing the components of a circuit, there are $2$ other single word commands that can be entered: spice and end. The end is the simplest to understand and implement. When the end command is entered, the program should print All Done and terminate. The spice command should print the spice description of the circuit entered so far. In the spice description, uppercase letters are used, components are numbered sequentially and DC is used in the description of voltage sources.