495. Teemo Attacking

public class Solution {    public int findPoisonedDuration(int[] timeSeries, int duration) {        if(timeSeries == null || timeSeries.length == 0) {            return 0;        }else if(timeSeries.length == 1) {            return duration;        }else {            int sum =0;            for(int i = 1; i < timeSeries.length;i++) {                if(timeSeries[i]-timeSeries[i-1] <= duration) {                    sum+=(timeSeries[i]-timeSeries[i-1]);                }else {                    sum += duration;                }            }            sum+=duration;            return sum;        }    }}