Submission #69126

#	Time	Username	Problem	Language	Result	Execution time	Memory
69126		Inovak	Port Facility (JOI17_port_facility)	C++14	0 / 100	2 ms	376 KiB

port_facility

#include <bits/stdc++.h>

#define fr first
#define sc second
#define pb push_back
#define mk make_pair
#define ll long long
#define OK puts("OK");
#define sz(s) (int)s.size()
#define all(s) s.begin(), s.end()

using namespace std;

const int N = 2e6+10;
const int mod = 1e9+7;

int n;
pair <int, int> p[N];
stack <int> a, b;
ll ans = 1;

int main() {
    scanf("%d", &n);
    for(int i = 1; i <= n; i++) {
        scanf("%d%d", &p[i].fr, &p[i].sc);
    }
    sort(p + 1, p + n + 1);
    for(int i = 1; i <= n; i++) {
        while(!a.empty() && a.top() < p[i].fr) a.pop();
        while(!b.empty() && b.top() < p[i].fr) b.pop();

        ll y = 2;
        bool fl = 0;
        if(!a.empty() && a.top() < p[i].sc) y--;
        else a.push(p[i].sc), fl = 1;

        if(!b.empty() && b.top() < p[i].sc) y--;
        else if(!fl) b.push(p[i].sc);

        if(y == 0) {puts("0");return 0;}
        ans = ans * y % mod;
    }
    cout << ans << endl;
}

Compilation message (stderr)

port_facility.cpp: In function 'int main()':
port_facility.cpp:23:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
port_facility.cpp:25:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &p[i].fr, &p[i].sc);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22