Submission #958851

#	Time	Username	Problem	Language	Result	Execution time	Memory
958851		Pring	Three Friends (BOI14_friends)	C++17	100 / 100	8 ms	9076 KiB

friends

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

#ifdef MIKU
string dbmc = "\033[1;38;2;57;197;187m", dbrs = "\033[0m";
#define debug(x...) cout << dbmc << "[" << #x << "]: ", dout(x)
void dout() { cout << dbrs << endl; }
template <typename T, typename ...U>
void dout(T t, U ...u) { cout << t << (sizeof...(u) ? ", " : ""); dout(u...); }
#else
#define debug(...) 39
#endif

#define int long long
#define fs first
#define sc second
#define mp make_pair
#define FOR(i, j, k) for (int i = j, Z = k; i < Z; i++)
typedef pair<int, int> pii;

int n;
string s;
string ans[2];
bitset<2> b;

void SOLVE(int id, string l, string r) {
    int x = 0;
    for (auto &i : r) {
        if (x < l.size() && i == l[x]) x++;
    }
    if (x == l.size()) {
        b[id] = 1;
        ans[id] = l;
        return;
    }
    b[id] = 0;
}

void miku() {
    cin >> n >> s;
    if (n % 2 == 0) {
        cout << "NOT POSSIBLE" << '\n';
        return;
    }
    SOLVE(0, s.substr(0, n / 2), s.substr(n / 2, n - n / 2));
    SOLVE(1, s.substr(n / 2 + 1, n - n / 2 - 1), s.substr(0, n / 2 + 1));
    if (!b[0] && !b[1]) {
        cout << "NOT POSSIBLE" << '\n';
        return;
    }
    if (b[0] && b[1]) {
        cout << (ans[0] == ans[1] ? ans[0] : "NOT UNIQUE") << '\n';
        return;
    }
    cout << (b[0] ? ans[0] : ans[1]) << '\n';
}

int32_t main() {
    cin.tie(0) -> sync_with_stdio(false);
    cin.exceptions(cin.failbit);
    miku();
    return 0;
}

Compilation message (stderr)

friends.cpp: In function 'void SOLVE(long long int, std::string, std::string)':
friends.cpp:29:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         if (x < l.size() && i == l[x]) x++;
      |             ~~^~~~~~~~~~
friends.cpp:31:11: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |     if (x == l.size()) {
      |         ~~^~~~~~~~~~~

• Subtask 1: 35 / 35
• Subtask 2: 65 / 65