Leetcode268.java

packagecom.company;

publicclassLeetcode268 {
publicstaticvoidmain(String[] args) {
int[] arr={9,6,4,2,3,5,7,0,1};
intans=missing(arr);
System.out.println(ans);;
 }


staticintmissing(int[] arr){
sort(arr);

for(inti=0;i<arr.length;i++){
if(arr[i]!=i){
returni;
 }
 }
returnarr.length;
 }



staticvoidsort(int[] arr) {
inti = 0;
while (i < arr.length) {
intcharIndex = arr[i];
if (arr[i] > arr.length-1) {
i++;
continue;
 }

if (arr[i] != arr[charIndex]) {
swap(arr, i, charIndex);
 } else {
i++;
 }
 }
 }

staticvoidswap(int[] arr, inta, intb){
inttemp=arr[a];
arr[a]=arr[b];
arr[b]=temp;
 }
}