Submission #95195

#	Time	Username	Problem	Language	Result	Execution time	Memory
95195		win11905	Lightning Rod (NOI18_lightningrod)	C++11	66 / 100	2069 ms	138944 KiB

Main

/**
 * 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};

int n;
stack<pii> stk;
bool check_cover(pii a, pii b) {
    return abs(a.x - b.x) <= a.y - b.y;
}

int32_t main() {
    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);
    }
    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());
}

Compilation message (stderr)

lightningrod.cpp: In function 'int32_t main()':
lightningrod.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
lightningrod.cpp:31:14: 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
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 26 / 26
• Subtask 6: 0 / 10
• Subtask 7: 0 / 20