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Logic Level 4

\[\LARGE 9 \ \ \ 8 \ \ \ 7 \ \ \ 6 \ \ \ 5 \ \ \ 4 \ \ \ 3 \ \ \ 2 \ \ \ 1 \ \ \ = \ \ 100\]

Without touching the right side of the equation, find a way to make the equation above true. You are only allowed to use mathematical operators like addition and subtraction only.

Find a possible way to make the above equation true such that you used the least number of mathematical operators. Let \(A\) denote the number of addition signs used and \(S\) denote the number of subtraction sign used. Find the value of \(3A+4S\).

Details And Assumptions:

As an explicit example if the equation \(9+8-7-6-5+4+3-2-1=100\) is true, then you have used 4 addition signs and 5 subtraction signs. So \(A=4 \ , \ S=5\).
You can combine the digits as well.That is \(98765+43+21\).
You must keep the digits in order (from left to right).That is \(9+87+65+4321\) is valid but \(9+78+56+3421\) is not allowed.

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