```
class Solution {
func findComplement(_ num: Int) -> Int {
var compNo = ""
var complement = 0
let bitNo = String(num, radix:2)
for i in 0..<bitNo.characters.count {
let index = bitNo.index(bitNo.startIndex, offsetBy: i)
//print(bitNo[index])
if bitNo[index] == "0" {
compNo += "1"
}else {
compNo += "0"
}
}
complement = Int(compNo, radix:2)!
let answer = complement
print(answer)
return answer
}
}
Solution().findComplement(5)
```