Need a Formula to Add a Row of Numbers and Then Subtract if from Another Cell Amount

I have a row A through N. In cell A1, have a dollar amount. In cells C1 through N1, I have different dollar amounts. In cell O1, I want to have a formula that will take the dollar figure in A1 and subtract from that amount the total of all the amounts in cells C1 thorugh N1. But I don't know how to write that formula.

Let's say I've got $100 in A1, and then in C1 through N1, I have $2, $3, $4, etc. for a total amount of $94 in cells C1 through N1. I'd like to have a formula in O1 that would show $6.

I hope this is clear. I'd appreciate any help about how to write up that formula in cell O1.

Jason

Perfect! Thanks very much for such a quick response.

Jason