贴上代码

#include<iostream>
#include<fstream>
#include<algorithm>
using namespace std;
int n,s=1,t,a[100000];
int one(int x)
{
	int L=0,R=100001;
	while(L+1<R)
	{
		int mid=(L+R)/2;
		if(a[mid]<=x) L=mid;
		else R=mid;
	}
	if(L==x) return 1;
	return 0;
}
int main()
{
	freopen("d.in","r",stdin);
	freopen("d.out","w",stdout);
	cin>>n;
	for(int i=1;i<=100000;i++)
	{
		s=s+t;
		t++;
		a[i]=s;
	}
	for(int i=1;i<=n;i++)
	{
		int x;
		cin>>x;
		cout<<one(x)<<endl;
	}
	return 0;
}