expression - Java modulus operator - why is the result unexpected? -

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i understand in modulus 17/12 = 5.

why 4+17 % 2-1 value 4, , (4+17) % 2-1 value 0?

operator precedence. % evaluated first, so

4 + 17 % 2 - 1

is equivalent to

4 + (17 % 2) - 1

17%2 == 1 yields 4+1-1 equals 4

when place brackets there, change order of evaluation:

(4+17) % 2 - 1

is equivalent to

21 % 2 - 1

which again, because of % having higher precendence -, yields

1 - 1

which 0


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