c# - represent array of integers in bit field

Question

i have an array of integer like

int [] intArray;
intArray = new int[3] { 1, 2 , 40 , 45 , 50};

the array contains numbers from 1- to 50

i want to convert this array to one bit represent like

100001000010000............11

who can i do this in c# ?

cdhowie · Accepted Answer · 2010-11-17 16:57:36Z

2

long bitField = 0;

foreach (int bit in intArray)
    bitField |= 1l << (bit - 1);

This answer assumes 1-based bit numbers as per your question. If you would like 0 to refer to the first bit, simply change (bit - 1) to bit.

answered Nov 17, 2010 at 16:52

cdhowie

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1 Comment

An alternative: long bitField = intArray.Aggregate(0l, (a, x) => a | (1l << (x - 1)));