Problem Link : https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=2950
Solution Idea:
The tricky part in this problem statement is this –
” Can Brenda drive her car from Dawson City to Delta Junction and back? ”
So Brenda need to reach her destination and return his start point. So just take input all the points and sort then in acceding order and check that the distance between two consecutive points is less than or equal to 200 or not. If it’s not then the ans will be impossible and if the 2*(distance between the last point and and destination) >200 the ans will be impossible. Otherwise the ans is possible.
/*
If opportunity doesn't knock, build a door.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|.|S|.|R|.|A|.|S|.|A|.|M|.|K|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Success is how high you bounce when you hit bottom.
*/
#include <bits/stdc++.h>
#define pii pair <int,int>
#define pll pair <long long,long long>
#define sc scanf
#define pf printf
#define Pi 2*acos(0.0)
#define ms(a,b) memset(a, b, sizeof(a))
#define pb(a) push_back(a)
#define MP make_pair
#define db double
#define ll long long
#define EPS 10E-10
#define ff first
#define ss second
#define sqr(x) (x)*(x)
#define D(x) cout<<#x " = "<<(x)<<endl
#define VI vector <int>
#define DBG pf("Hi\n")
#define MOD 1000000007
#define CIN ios_base::sync_with_stdio(0); cin.tie(0)
#define SZ(a) (int)a.size()
#define sf(a) scanf("%d",&a)
#define sfl(a) scanf("%lld",&a)
#define sff(a,b) scanf("%d %d",&a,&b)
#define sffl(a,b) scanf("%lld %lld",&a,&b)
#define sfff(a,b,c) scanf("%d %d %d",&a,&b,&c)
#define sfffl(a,b,c) scanf("%lld %lld %lld",&a,&b,&c)
#define stlloop(v) for(__typeof(v.begin()) it=v.begin();it!=v.end();it++)
#define loop(i,n) for(int i=0;i<n;i++)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define RREP(i,a,b) for(int i=a;i>=b;i--)
#define TEST_CASE(t) for(int z=1;z<=t;z++)
#define PRINT_CASE printf("Case %d: ",z)
#define CASE_PRINT cout<<"Case "<<z<<": "
#define all(a) a.begin(),a.end()
#define intlim 2147483648
#define infinity (1<<28)
#define ull unsigned long long
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) ((a)*((b)/gcd(a,b)))
using namespace std;
/*----------------------Graph Moves----------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1}; // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1}; // Kings Move
//const int fx[]={-2, -2, -1, -1, 1, 1, 2, 2}; // Knights Move
//const int fy[]={-1, 1, -2, 2, -2, 2, -1, 1}; // Knights Move
/*------------------------------------------------*/
/*-----------------------Bitmask------------------*/
//int Set(int N,int pos){return N=N | (1<<pos);}
//int reset(int N,int pos){return N= N & ~(1<<pos);}
//bool check(int N,int pos){return (bool)(N & (1<<pos));}
/*------------------------------------------------*/
int main()
{
// freopen("in.txt","r",stdin);
///freopen("out.txt","w",stdout);
int n;
while(cin>>n && n)
{
vector<int>v;
loop(i,n)
{
int a;
cin>>a;
v.pb(a);
}
sort(all(v));
bool test=0;
REP(i,1,n)
{
if(v[i]-v[i-1]>200)
{
cout<<"IMPOSSIBLE"<<endl;
test=1;
break;
}
}
if(test==1) continue;
if((1422-v[n-1])*2>200) test=1;
if(test==0)
cout<<"POSSIBLE"<<endl;
else
cout<<"IMPOSSIBLE"<<endl;
}
return 0;
}