Submission #1053089

#	Time	Username	Problem	Language	Result	Execution time	Memory
1053089		elazarkoren	Sprinklers (CEOI24_sprinklers)	C++17	3 / 100	10 ms	2396 KiB

Main

#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vii;

const int MAX_N = 1e5 + 5;

ll s[MAX_N], f[MAX_N];
int ri[MAX_N];
int n, m;

bool Solve(int k) {
    int i = 0, j = 0;
//    ll rightest = -1;
    vi leftest(n);
    while (i < n && j < m) {
        if (abs(f[j] - s[i]) > k) return 0;
        if (f[j] >= s[i]) {
            leftest[i] = f[j] - s[i] <= k ? j : -1;
            while (j < m && f[j] - s[i] <= k) j++;
            ri[i] = 1;
//            rightest = s[i] + k;
            i++;
            continue;
        }
        ri[i] = 0;
        if (i && leftest[i - 1] != -1 && s[i] - f[leftest[i - 1]] <= k) {
            leftest[i] = leftest[i - 1];
            while (j < m && f[j] - s[i - 1] <= k) j++;
            ri[i - 1] = 1;
//            rightest = s[i - 1] + k;
        } else {
            leftest[i] = j;
        }
        while (j < m && f[j] <= s[i] && s[i] - f[j] <= k) j++;
        i++;
    }
    return j == m;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    for (int i = 0; i < n; i++) cin >> s[i];
    for (int i = 0; i < m; i++) cin >> f[i];
    int begin = 0, end = 1e9 + 1;
    while (begin < end) {
        int mid = (begin + end) >> 1;
        if (Solve(mid)) end = mid;
        else begin = mid + 1;
    }
    if (!Solve(end)) {
        cout << -1 << '\n';
        return 0;
    }
    cout << end << '\n';
    for (int i = 0; i < n; i++) {
        cout << (ri[i] ? 'R' : 'L');
    }
}

• Subtask 0: 0 / 0
• Subtask 1: 3 / 3
• Subtask 2: 0 / 6
• Subtask 3: 0 / 17
• Subtask 4: 0 / 27
• Subtask 5: 0 / 47