Submission #259396

#	Time	Username	Problem	Language	Result	Execution time	Memory
259396		doowey	Match (CEOI16_match)	C++14	10 / 100	1 ms	384 KiB

match

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

const int AL = 26;
const int N = (int)1e5 + 10;
int id[N];
int pref[N];

map<int, vector<int>> gg[AL];

char sol[N];

void compute(int l, int r){
    if(l > r) return;
    int mask = pref[l - 1];
    int vi = upper_bound(gg[id[l]][mask].begin(), gg[id[l]][mask].end(), r) - gg[id[l]][mask].begin();
    vi -- ;
    if(vi < 0 || vi >= gg[id[l]][mask].size()) {
        cout << "-1\n";
        exit(0);
    }
    int idx = gg[id[l]][mask][vi];
    if(idx > l && idx <= r){
        sol[l] = '(';
        sol[idx] = ')';
        compute(l + 1, idx - 1);
        compute(idx + 1, r);
    }
    else{
        cout << "-1\n";
        exit(0);
    }
}

int main(){
    fastIO;
    string t;
    cin >> t;
    char f;
    int n = t.size();
    for(int i = 1; i <= n; i ++ ){
        f = t[i - 1];
        id[i] = f - 'a';
        pref[i]=(pref[i-1] ^ (1 << id[i]));
        gg[id[i]][pref[i]].push_back(i);
    }
    compute(1, n);
    for(int i = 1; i <= n; i ++ )
        cout << sol[i];
    cout << "\n";
    return 0;
}

Compilation message (stderr)

match.cpp: In function 'void compute(int, int)':
match.cpp:27:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(vi < 0 || vi >= gg[id[l]][mask].size()) {
                  ~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 27
• Subtask 3: 0 / 63