Submission #1445290

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define MOD 1e9 + 7

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);

    int n,k,mx = 0;
    bool pos = false;

    cin >> n >> k;

    vector<int> a(n);
    map<int,bool> m;

    for(int i = 0;i < n;i++){ cin >> a[i]; mx = max(mx,a[i]); if(a[i]==k) pos = true; m[a[i]] = true; }

    if(pos){ cout << "POSSIBLE"; return 0; }
    if(mx<k){ cout << "IMPOSSIBLE"; return 0; }

    for(int i = 0;i < n-1;i++)
    {
        int d = abs(a[i]-a[i+1]);
        if(!m[d]){ cout << "POSSIBLE"; return 0; }
    }

    cout << "IMPOSSIBLE";
}

Submission Info

Judge Result