Submission #1680385

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Source Code Expand

#include <bits/stdc++.h>
 
#define _overload(_1,_2,_3,name,...) name
#define _rep(i,n) _range(i,0,n)
#define _range(i,a,b) for(int i=(int)(a);i<(int)(b);++i)
#define rep(...) _overload(__VA_ARGS__,_range,_rep,)(__VA_ARGS__)
 
#define _rrep(i,n) _rrange(i,n,0)
#define _rrange(i,a,b) for(int i=(int)(a)-1;i>=(int)(b);--i)
#define rrep(...) _overload(__VA_ARGS__,_rrange,_rrep,)(__VA_ARGS__)
 
#define _all(arg) begin(arg),end(arg)
#define uniq(arg) sort(_all(arg)),(arg).erase(unique(_all(arg)),end(arg))
#define getidx(ary,key) lower_bound(_all(ary),key)-begin(ary)
#define clr(a,b) memset((a),(b),sizeof(a))
#define bit(n) (1LL<<(n))
 
// #define DEBUG
 
#ifdef DEBUG
    #define dump(...) fprintf(stderr, __VA_ARGS__)
#else
    #define dump(...)
#endif
 
template<class T>bool chmax(T &a, const T &b) { return (a<b)?(a=b,1):0;}
template<class T>bool chmin(T &a, const T &b) { return (b<a)?(a=b,1):0;}
 
using namespace std;
using ll=long long;
using vi=vector<int>;
using vll=vector<ll>;
 
const double EPS = 1e-10;
const double PI = acos(-1.0);
const ll inf =1LL << 62;
const ll mod=1000000007LL;
const int dx[4]={1,0,-1,0};
const int dy[4]={0,1,0,-1};
 
 
ll extgcd(ll a,ll b,ll& x,ll& y){x=1,y=0;ll g=a;if(b!=0) g=extgcd(b,a%b,y,x),y-=a/b*x;return g;}
ll ADD(const ll &a, const ll &b,const ll &mod) { return (a+b)%mod;}
ll SUB(const ll &a, const ll &b,const ll &mod) { return (a-b+mod)%mod;}
ll MUL(const ll &a, const ll &b,const ll &mod) { return (1LL*a*b)%mod;}
ll DIV(const ll &a, const ll &b,const ll &mod) {ll x,y; extgcd(b,mod,x,y);return MUL(a,(x+mod)%mod,mod);}
 
random_device rd;
mt19937 mt(rd());
uniform_int_distribution<int> dice(1,6);
uniform_real_distribution<double> score(0.0,10.0);

int main(void){
    cin.tie(0);
    ios::sync_with_stdio(false);

    int n, K; cin >> n >> K;
    if(n == K){
        cout << endl;
        return 0;
    }
    vi a(K); for(auto& e : a) cin >> e, e--;
    set<int> s(_all(a));
    vector<string> in(n); for(auto& e : in) cin >> e;
    int ri = a[0];
    for(auto& i : a){
        if(in[i].size() > in[ri].size()){
            ri = i;
        }
    }
    vi ord(n);
    {
        using Elem = tuple<int, int>;
        vector<Elem> tbl(n);
        rep(i, n) tbl[i] = Elem((int)in[i].size(), i);
        sort(_all(tbl), greater<Elem>());
        rep(i, n) ord[i] = get<1>(tbl[i]);
    }

    int res = -1;
    rep(l, 1, (int)1e5 + 5){
        int cnt = 0;
        bool other = false;

        if((int)in[ri].size() < l) break;
        char c = in[ri][l - 1];

        rep(_, n){
            int i = ord[_];
            if((int)in[i].size() < l) break;
            if(in[i][l - 1] == c){
                if(s.find(i) != end(s)) cnt++;
                else {
                    other = true;
                    break;
                }
            }
        }

        if(not other and cnt == (int)s.size()){
            res = l;
            break;
        }
    }

    if(res == -1){
        cout << res << endl;
    }
    else {
        cout << in[ri].substr(0, res) << endl;
    }

    return 0;
}

Submission Info

Judge Result