#include<bits/stdc++.h>
#define N 1919810
#define mod 998245353
using namespace std;

inline void read(int &x) {bool neg = false;x = 0;char ch = 0;while (ch < '0' || ch > '9') {if (ch == '-') neg = true;ch = getchar();}if (neg) {while (ch >= '0' && ch <= '9') {x = x * 10 + ('0' - ch);ch = getchar();}} else {while (ch >= '0' && ch <= '9') {x = x * 10 + (ch - '0');ch = getchar();}}return;}

template <typename T> inline void write(T x) {if (x < 0) x = -x, putchar('-');if (x > 9) write(x / 10);putchar(x % 10 + 48);}

int n,idx[N];

signed main(){
	freopen("kmpp.in","r",stdin);freopen("kmpp.out","w",stdout);
	read(n);
	while(n--){
		read(idx[n]);
	}
	cout<<"Impossible";
	return 0;
}