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Try input: 100 0 75000 2
0 .10
99 .5
-1 0 0 0 AC output: 100 months

hi, I didn't pass this test case. I want to know why, can you explain for me? thanks.
I think during month 1 to 98, the depreciation is zero. and month 99 and 100, depreciation is 0.5. Right ? Wrong? and My program result for ...