Submission #1264151

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264151		sohamsen15	Lightning Rod (NOI18_lightningrod)	C++20	100 / 100	519 ms	156400 KiB

Main

#include <iostream>
using namespace std;
using ll = long long;

const int BUF_SZ = 1 << 15;

inline namespace Input {
    char buf[BUF_SZ];
    int pos;
    int len;
    char next_char() {
        if (pos == len) {
            pos = 0;
            len = (int)fread(buf, 1, BUF_SZ, stdin);
            if (!len) { return EOF; }
        }
        return buf[pos++];
    }

    int read_int() {
        int x;
        char ch;
        int sgn = 1;
        while (!isdigit(ch = next_char())) {
            if (ch == '-') { sgn *= -1; }
        }
        x = ch - '0';
        while (isdigit(ch = next_char())) { x = x * 10 + (ch - '0'); }
        return x * sgn;
    }
}

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

    int n, ans = 0, x, y; n = read_int(); if (n == 1) { cout << 1; return 0; }
    int a[n], b[n], maxal[n], minbr[n];
    for (int i = 0; i < n; i++) { x = read_int(); y = read_int(); a[i] = x + y, b[i] = x - y; }
    maxal[0] = a[0]; for (int i = 1; i < n; i++) maxal[i] = max(maxal[i - 1], a[i]);
    minbr[n - 1] = b[n - 1]; for (int i = n - 2; i >= 0; i--) minbr[i] = min(minbr[i + 1], b[i]);
    ans += (b[0] < minbr[1]) + (a[n - 1] > maxal[n - 2]);
    for (int i = 1; i < n - 1; i++) ans += (b[i] < minbr[i + 1] && a[i] > maxal[i - 1]);
    cout << ans;
}

• Subtask 1: 4 / 4
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 26 / 26
• Subtask 6: 10 / 10
• Subtask 7: 20 / 20