Submission #23672

#	Time	Username	Problem	Language	Result	Execution time	Memory
23672		rubabredwan	Port Facility (JOI17_port_facility)	C++14	22 / 100	103 ms	19568 KiB

port_facility

/*  Bismillahir Rahmanir Rahim  */

#include <bits/stdc++.h>

using namespace std;

const int N = 2005;

int n;
int st[N], en[N];
int vis[N], flag, col[N];
vector<int>g[N];

void dfs(int at){
    vis[at] = 1;
    for(auto u : g[at]){
        if(!vis[u]){
            col[u] = col[at] ^ 1;
            dfs(u);
        }
        if(col[u] == col[at]) flag = 1;
    }
}

int main(){
    scanf("%d", &n);
    for(int i=1;i<=n;i++) scanf("%d %d", &st[i], &en[i]);
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(st[j] < st[i] && st[i] < en[j] && en[i] > en[j]){
                g[i].push_back(j);
                g[j].push_back(i);
            }
        }
    }
    int comp = 0;
    for(int i=1;i<=n;i++){
        if(vis[i]) continue;
        col[i] = 0;
        dfs(i);
        ++comp;
    }
    if(flag) cout << 0 << endl;
    else{
        long long mod = 1e9 + 7;
        long long ret = 1LL;
        for(int i=1;i<=comp;i++){
            ret *= 2LL;
            ret %= mod;
        }
        cout << ret << endl;
    }
	return 0;
}

Compilation message (stderr)

port_facility.cpp: In function 'int main()':
port_facility.cpp:26:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
port_facility.cpp:27:57: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++) scanf("%d %d", &st[i], &en[i]);
                                                         ^

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