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// +build gccgo !amd64 appengine
package bits
// Ctz counts trailing zeroes
func Ctz(x uint64) uint64 {
if x == 0 {
return 64
}
var n uint64
if (x & 0x00000000FFFFFFFF) == 0 {
n = n + 32
x = x >> 32
}
if (x & 0x000000000000FFFF) == 0 {
n = n + 16
x = x >> 16
}
if (x & 0x00000000000000FF) == 0 {
n = n + 8
x = x >> 8
}
if (x & 0x000000000000000F) == 0 {
n = n + 4
x = x >> 4
}
if (x & 0x0000000000000003) == 0 {
n = n + 2
x = x >> 2
}
if (x & 0x0000000000000001) == 0 {
n = n + 1
}
return n
}
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