keep笔试第一题不能全部通过哪里错了？？？

import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;
import java.util.Scanner;

public class Keep {
public static void main(String[] args) {
//输入
Scanner sc = new Scanner(System.in);
String s =sc.nextLine();
ArrayList<Interval> intervals= new ArrayList<>();
String [] split= s.split(" ");
for(int i=0;i<split.length;i++){
String[] ss= split[i].split(",");
Interval interval= new Interval();
interval.start=Integer.valueOf(ss[0]);
interval.end=Integer.valueOf(ss[1]);
intervals.add(interval);
}


int flag=0;
intervals.sort(new Comparator<Interval>() {

@Override
public int compare(Interval o1, Interval o2) {
return o1.start==o2.start?o1.end-o2.end:o1.start-o2.start;
}
});
for(int i=0;i<intervals.size()-1;i++){
if(intervals.get(i+1).start<intervals.get(i).end){
flag=1;
}
//加上此段代码通过率80%，不加40%
// if(intervals.get(i+1).start==intervals.get(i).start){
// flag=1;
// }
}
if(flag==1){
System.out.println("flase");

}else{
System.out.println("true");
}

}
}

class Interval {
int start;
int end;

Interval() {
start = 0;
end = 0;
}

Interval(int s, int e) {
start = s;
end = e;
}
}