oj.uz

Submission #95193

# Submission time Handle Problem Language Result Execution time Memory
95193 2019-01-28T12:59:36 Z win11905 Lightning Rod (NOI18_lightningrod) C++11
66 / 100
 2000 ms 131972 KB 
/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author win11905
 */

#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define vi vector<int>
#define iii tuple<int, int, int>
#define long long long
#define pii pair<int, int>
#define x first
#define y second
using namespace std;
const long MOD = 1e9+7, LINF = 1e18 + 1e16;
const int INF = 1e9+1;
const double EPS = 1e-10;
const int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};


class lightningrod {
private:
    int n;
    stack<pii> stk;
    bool check_cover(pii a, pii b) {
        return abs(a.x - b.x) <= a.y - b.y;
    }
public:
    void solve(istream& cin, ostream& cout) {
        scanf("%d", &n);
        vector<pii> vec;
        for(int i = 0, a, b; i < n; ++i) {
            scanf("%d %d", &a, &b);
            vec.emplace_back(a, b);
        }
        sort(vec.begin(), vec.end(), [&](const pii &a, const pii &b) {
            if(a.x == b.x) return a.y > b.y;
            return a.x < b.x;
        });
        for(auto v : vec) {
            if(stk.empty()) {
                stk.emplace(v);
                continue;
            }
            if(check_cover(stk.top(), v)) continue;
            while(!stk.empty() && check_cover(v, stk.top())) stk.pop();
            stk.emplace(v);
        }
        printf("%d\n", (int)stk.size());
    }
};

class Solver {
public:
    void solve(std::istream& in, std::ostream& out) {
        lightningrod *obj = new lightningrod();
        obj->solve(in, out);
    }
};

int32_t main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    Solver solver;
    std::istream& in(std::cin);
    std::ostream& out(std::cout);
    solver.solve(in, out);
    return 0;
}

Compilation message

lightningrod.cpp: In member function 'void lightningrod::solve(std::istream&, std::ostream&)':
lightningrod.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &n);
         ~~~~~^~~~~~~~~~
lightningrod.cpp:34:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d", &a, &b);
             ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2076 ms 131860 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 380 KB Output is correct
7 Correct 2 ms 376 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 380 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct

Subtask #4
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 380 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 376 KB Output is correct
13 Correct 3 ms 376 KB Output is correct

Subtask #5
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 380 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 376 KB Output is correct
13 Correct 3 ms 376 KB Output is correct
14 Correct 59 ms 2540 KB Output is correct
15 Correct 56 ms 2536 KB Output is correct
16 Correct 54 ms 2528 KB Output is correct

Subtask #6
0 / 10.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2066 ms 131972 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #7
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2076 ms 131860 KB Time limit exceeded
2 Halted 0 ms 0 KB -