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/* http://www.tbray.org/ongoing/When/200x/2003/03/22/Binary */
/* returns first target if more than one have same value */
static public int search(int [] array, int target)
{
int high = array.length, low = -1, probe;
while (high - low > 1)
{
probe = (high + low) / 2;
if (array[probe] < target)
low = probe;
else
high = probe;
}
if (high == array.length || array[high] != target)
return -1;
else
return high;
}
/* returns last target if more than one have same value */
static public int search2(int [] array, int target)
{
int high = array.length, low = -1, probe;
while (high - low > 1)
{
probe = (high + low) / 2;
if (array[probe] > target)
high = probe;
else
low = probe;
}
if (low == -1 || array[low] != target)
return -1;
else
return low;
}
static public int [] range(int [] array, int floor, int ceiling)
{
int [] answer = new int[2];
int high, low, probe;
// work on floor
high = array.length; low = -1;
while (high - low > 1)
{
probe = (high + low) / 2;
if (array[probe] < floor)
low = probe;
else
high = probe;
}
answer[0] = low;
// work on ceiling
high = array.length; low = -1;
while (high - low > 1)
{
probe = (high + low) / 2;
if (array[probe] > ceiling)
high = probe;
else
low = probe;
}
answer[1] = high;
return answer;
}
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