Submission #1865585

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Source Code Expand

#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define forE(i,x) for(int i=head[x];i!=-1;i=ne[i])
using namespace std;
typedef long long i64;
typedef unsigned long long u64;
typedef unsigned u32;
typedef pair<int,int> pin;
#define mk(a,b) make_pair(a,b)
#define lowbit(x) ((x)&(-(x)))
#define sqr(a) ((a)*(a))
#define clr(a) (memset((a),0,sizeof(a)))
#define ls ((x)<<1)
#define rs (((x)<<1)|1)
#define mid (((l)+(r))>>1)
#define pb push_back
#define w1 first
#define w2 second
inline void read(int &x){
	x=0;int f=1;char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
	x*=f;
}
inline void judge(){
	freopen("in.txt","r",stdin);
	freopen("out.txt","w",stdout);
}
/*******************************head*******************************/
const int maxn=100005;
int a[maxn],n;
int main(){
	read(n);rep(i,1,n)read(a[i]);
	int maxi=0;
	rep(i,1,n)maxi=max(maxi,a[i]);
	int cnt=0;
	rep(i,1,n)cnt+=a[i]==maxi;
	if(cnt<2){
		puts("Impossible");
		return 0;
	}
	int flag=1;int mini=(maxi+1)/2;
	if(maxi&1)flag++;
	rep(i,1,n){
		if(a[i]<mini){
			puts("Impossible");
			return 0;
		}
		if(a[i]==mini){
			if(!flag){
				puts("Impossible");
				return 0;
			}
			flag--;
		}
	}
	puts("Possible");
	return 0;
}

Submission Info

Judge Result