Submission #1735985

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Source Code Expand

#include<set>
#include<map>
#include<deque>
#include<queue>
#include<stack>
#include<cmath>
#include<ctime>
#include<bitset>
#include<string>
#include<vector>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<complex>
#include<iostream>
#include<algorithm>
#define ll long long
using namespace std;

const int maxn  = 2100;

int n,A,B;
int t[maxn],tp;
char str[110];
bool v[maxn];

int main()
{
	//freopen("tmp.in","r",stdin);
	//freopen("tmp.out","w",stdout);
	
	cin>>A>>B; n=A+B;
	if(A<=B) { cout<<"Impossible"<<endl; return 0; }
	
	for(int i=2;i<=n;i++)
	{
		if(!tp) t[++tp]=i;
		else
		{
			cout<<"? "<<t[tp]<<" "<<i<<endl;
			cin>>str;
			if(str[0]=='N') tp--;
			else t[++tp]=i;
		}
	}
	int x=t[tp]; v[x]=true;
	for(int i=1;i<=n;i++) if(i!=x)
	{
		cout<<"? "<<x<<" "<<i<<endl;
		cin>>str;
		v[i]=str[0]=='Y'?true:false;
	}
	cout<<"! ";
	for(int i=1;i<=n;i++) cout<<(v[i]?1:0);
	cout<<endl;
	
	return 0;
}

Submission Info

Judge Result