原題鏈接:https://leetcode-cn.com/problems/linked-list-components/
線性掃描
int numComponents(ListNode* head, vector<int>& G) {
int ans=0;
bool flag=false;
set<int> s(G.begin(),G.end());
while(head!=NULL){
int value=head->val;
if(s.find(value)!=s.end()){
if(!flag){
flag=true;
ans++;
}
} else{
flag=false;
}
head=head->next;
}
return ans;
}