Isn't this problem easy?

```
public class Solution {
public void sortColors(int[] nums) {
for(int i=0; i<nums.length-1; i++){
for(int j=i+1;j<nums.length; j++){
if(nums[j]-nums[i]<0){
int temp = nums[i];
nums[i] = nums[j];
nums[j] = temp;
}
}
}
}
}
```