oj.uz

Submission #1100585

# Submission time Handle Problem Language Result Execution time Memory
1100585 2024-10-14T09:26:23 Z crafticat Sprinklers (CEOI24_sprinklers) C++17
6 / 100
 898 ms 12064 KB 
#include <bits/stdc++.h>

using namespace std;
template<typename T>
using V = vector<T>;
using vi = V<int>;
using vb = V<bool>;
using pi = pair<int,int>;


vi water, flowers;
V<bool> types;
set<int> problems;
constexpr int inf = 1e9 + 7;

bool between(int l, int r) {
    auto it = problems.upper_bound(l);
    if (it == problems.end() || *it >= r) return true;
    return false;
}

int pos(V<V<int>> &dp, int i, int lastR, int r) {
    int leftR = -1;
    if (i >= 0) {
        for (int j = 0; j < 3; ++j) {
            if (j == 0) leftR = water[i];
            if (j == 1 && i - 1 >= 0) leftR = water[i - 1] + r;
            if (j == 2) leftR = water[i] + r;
            if (dp[i][j] == -1) continue;
            if (between(leftR, lastR)) return j;
        }
    } else {
       return between(0, lastR) ? 0 : -1;
    }
    return -1;
}

bool ok(int r) {
    V<V<int>> dp(water.size() + 1, vi(3,-1));

    for (int i = 0; i < water.size(); ++i) {
        for (int j = 0; j < 3; ++j) {
            int lastR = -1;
            if (j == 0) lastR = water[i] - r;
            if (j == 1 && between(water[i - 1] + r, water[i] - r)) lastR = water[i] - r;
            if (j == 2) lastR = water[i];
            dp[i][j] = pos(dp,i - 1 + (j == 1 ? -1 : 0),lastR, r);
        }
    }

    // Backtrace
    int last = dp[water.size() - 1][2];
    int i = water.size() - 1;
    if (last == -1) return false;
    while (last != -1) {
        if (last == 1) {
            types.push_back(false);
            types.push_back(true);
            if (i - 2 < 0) return true;
            last = dp[i - 2][last];
            i -= 2;
        } else {
            types.push_back(last == 2);
            if (i - 1 < 0) return true;
            last = dp[i - 1][last];
            i--;
        }
    }
    return true;
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);

    int n, m; cin >> n >> m;
    water.resize(n + 1);
    flowers.resize(m);

    for (int i = 0; i < n; ++i) {
        cin >> water[i];
        water[i]++;
    }
    water[n] = inf;
    for (int i = 0; i < m; ++i) {
        cin >> flowers[i];
        flowers[i]++;
        problems.insert(flowers[i]);
    }

    int l = 0, r = inf; // Last true
    while (r > l) {
        int mid = l + (r - l) / 2;
        if (ok(mid)) {
            r = mid;
        } else
            l = mid + 1;
    }

    types.clear();
    ok(l);
    if (l == inf) {
        cout << -1;
        return 0;
    }
    if (l == 0) l++;
    cout << l << "\n";
    types.pop_back();
    std::reverse(types.begin(), types.end());
    for (auto x : types) {
        cout << (x ? "R" : "L");
    }
    return 0;
}

Compilation message

Main.cpp: In function 'bool ok(int)':
Main.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |     for (int i = 0; i < water.size(); ++i) {
      |                     ~~^~~~~~~~~~~~~~

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Correct
2 Correct 0 ms 336 KB Correct

Subtask #1
0.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 336 KB Correct
2 Incorrect 19 ms 3660 KB User solution is incorrect
3 Halted 0 ms 0 KB -

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Correct
2 Correct 37 ms 3920 KB Correct
3 Correct 40 ms 1124 KB Correct
4 Correct 644 ms 12060 KB Correct
5 Correct 657 ms 12064 KB Correct
6 Correct 1 ms 336 KB Correct
7 Correct 1 ms 336 KB Correct
8 Correct 473 ms 8364 KB Correct
9 Correct 501 ms 8736 KB Correct
10 Correct 776 ms 10808 KB Correct
11 Correct 215 ms 7196 KB Correct
12 Correct 262 ms 7436 KB Correct
13 Correct 748 ms 10004 KB Correct
14 Correct 727 ms 10528 KB Correct
15 Correct 655 ms 10412 KB Correct
16 Correct 657 ms 9256 KB Correct

Subtask #3
0.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Correct
2 Correct 0 ms 336 KB Correct
3 Correct 1 ms 336 KB Correct
4 Correct 1 ms 336 KB Correct
5 Correct 1 ms 336 KB Correct
6 Incorrect 1 ms 504 KB User solution is incorrect
7 Halted 0 ms 0 KB -

Subtask #4
0.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Correct
2 Correct 135 ms 4444 KB Correct
3 Incorrect 898 ms 11488 KB Incorrect string length
4 Halted 0 ms 0 KB -

Subtask #5
0.0 / 47.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Correct
2 Correct 0 ms 336 KB Correct
3 Incorrect 19 ms 3660 KB User solution is incorrect
4 Halted 0 ms 0 KB -