Submission #5901453

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

#define repd(i,a,b) for (int i=(a);i<(b);i++)
#define rep(i,n) repd(i,0,n)
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
typedef long long ll;

const long long INF = 1LL << 60;

ll gcd(ll a, ll b) {
    if (b == 0) return a;
    return gcd(b, a % b);
}

int main()
{
    ll N, K;
    cin >> N >> K;

    vector<ll> A(N);

    rep(i, N) cin >> A[i];

    ll gcd_m = INF;
    ll max_n = A[0];
    repd(i, 1, N) {
        max_n = max(max_n, A[i]);
        gcd_m = min(gcd_m, gcd(A[i - 1], A[i]));
    }

    bool flag = false;

    if (K > max_n) {
        cout << "IMPOSSIBLE" << endl;
    }
    else {
        rep(i, N) {
            if (A[i] % gcd_m == K % gcd_m) {
                flag = true;
                break;
            }
        }
        if (flag) {
            cout << "POSSIBLE" << endl;
        }
        else {
            cout << "IMPOSSIBLE" << endl;
        }
    }

    return 0;
}

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