#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
// Yukicoder №4 おもりと天秤 ★★☆
// https://yukicoder.me/problems/no/4
// ***********************
// for debug
#define DEBUGd
// -----------

#define NOP do{}while(0)
#ifdef DEBUG
#define TRACE(...) do{printf(__VA_ARGS__);fflush(stdout);}while(0)
#define TRACECR do{putchar_unlocked('\n');fflush(stdout);}while(0)
#else
#define TRACE(...) NOP
#define TRACECR NOP
#endif

#define	mypc(d)	putchar_unlocked(d)
#define PRINCR mypc('\n')
#define NOCR(strig) do{char *p;p=strchr(strig,'\n');if(p)*p='\0';}while(0)
// The out-of-date function
#define	asctime(...)	asctime_s(...)
#define	ctime(...)		ctime_s(...)
#define	strlen(a)	mystr_len(a)
#define Possible(a) 	   printf("%s",((a)?"Possible":"Impossible"))
#define possible(a) 	   printf("%s",((a)?"possible":"impossible"))

// for stdio
#define GETLINE(str) do{char *p;fgets(str,sizeof(str),stdin);p=strchr(str,'\n');if(p)*p='\0';}while(0)
#define mygc(c) (c)=getchar_unlocked()
static char *GETWORD(char* str) {char c;char *cp;cp=&str[0];mygc(c);while(c!=EOF){if((c==' ')||(c=='\n'))break;*cp++=c;mygc(c);}*cp='\0';return &str[0];}
#define	GETINTS(a,b) {char s[34];int *ap=a;REP(i,b){GETWORD(s);*ap++=atoi(s);}}
static int GETLINEINT(void) {char s[34];GETLINE(s);return atoi(s);}
static int GETWORDINT(void) {char s[34];GETWORD(s);return atoi(s);}
static long GETWORDLONG(void) {char s[34];GETWORD(s);return atol(s);}
static long maxl(long a,long b){if(a>b){return a;}return b;}
#define mystr_len(str)    mystr_len_lim(str,9999)
static int mystr_len_lim(char *str,int lim){int i=0;do{if(str[i]=='\0')break;i++;}while(i<lim);return i;}
#define SWAP(type,a,b) do{type _c;_c=a;a=b;b=_c;}while(0)
#define REP(a,b) for(int a=0;a<(int)(b);++a)
// **************************
bool 	weight[100*102];
int		mono[100];
// **************************
int main( void ) {
	int	kosuu;
	int	val;
	int	sumw =0;

	kosuu = GETLINEINT();

	REP(i,100 * (kosuu + 1)) weight[i] = false;
	weight[0] = true;
	REP(i,kosuu) {
		val = GETWORDINT();
		sumw += val;
		mono[i] = val;
	}
    TRACE("sumw = %d\n", sumw );
	if( !(sumw & 1) ) {
        // あり得る取り合わせ全列挙
		REP(i,kosuu) {
			for(int k = i*100+100; k >=0; --k) {
				if( weight[ k ] ) weight[ k + mono[i] ] = true;
			}
		}
		TRACE("lp\n");
	} 
	possible( weight[ sumw / 2] );
	PRINCR;
	return 0;
}