CF1643补题记录

B
和上海那题异曲同工的构造题
补图真是个好东西

#include
using namespace std;
typedef long long ll;
const int N=55;
int t,n;
int a[N];

int main()
{
	int t;
	cin>>t;
	while(t--){
		vector<int>ans1,ans2;
		cin>>n;
		ll sum1=0,sum2=0,sum=0;
		for(int i=0;i<n;i++){
			cin>>a[i];
			if(i%2==0){
				sum1+=a[i]-1;
				ans1.push_back(a[i]);
				ans2.push_back(1); 
			}else{
				sum2+=a[i]-1;
				ans1.push_back(1);
				ans2.push_back(a[i]);
			}
			sum+=a[i];
		}
		//cout<
		if(sum1>sum2){
			for(int i=0;i<ans1.size();i++){
				cout<<ans1[i]<<" ";
			}
		}else{
			for(int i=0;i<ans2.size();i++){
				cout<<ans2[i]<<" ";
			}
		}
		cout<<endl;
	}
}

C
模拟题
我觉得模拟题就是要逻辑

#include
using namespace std;
typedef long long ll;
const int INF = 1e9+5;
const int N=1e5+5;
int t,n;
int tm[N],p[N];
bool check(int l,int r,int x){
	if(l>r) swap(l,r);
	return l<=x&&x<=r;
}
void solve()
{
	cin>>n;
	for(int i=0;i<n;i++){
		cin>>tm[i]>>p[i];
	}
	tm[n]=INF;
	int at=0,to=0,cnt=0;
	for(int i=0;i<n;i++){
		
		
		if(at==to) to=p[i];
		int lst=at;//at:next position   
		cout<<lst<<"   "<<at<<"->"<<to<<" "<<endl; 
		ll delt=tm[i+1]-tm[i];                                                             
		if(abs(to-at)<=delt) at=to;
		else at=to<at?at-delt:at+delt;
		
		if(check(lst,at,p[i])) cnt++;
	}
	//cout<<"***************"<
	cout<<cnt<<endl;
}
int main()
{
	cin>>t;
	while(t--){
		solve();
	} 
}