1-7 两个有序链表序列的交集 (20 分)

1 2 5 -1
2 4 5 8 10 -1

2 5

#include<iostream>
using namespace std;
int sum1[9999999],sum2[9999999],s1,s2,d1,d2;
int main(){
	int n,flag=0;
	while(cin>>n&&n!=-1){sum1[s1++]=n;}
    while(cin>>n&&n!=-1){sum2[s2++]=n;}
    while(d1!=s1&&d2!=s2){
		if(sum1[d1]==sum2[d2]){
			if(flag){cout<<" ";}
            flag=1;
			cout<<sum1[d1];
			d1++;
			d2++;
		}else{
			if(sum1[d1]<sum2[d2]){d1++;}
            else{d2++;}
		}
	}if(flag==0){cout<<"NULL";}
	return 0;
}