#include <bits/stdc++.h>
#define ff first
#define ss second
using namespace std;
typedef pair<int, int> pii;
set<int> st_up, st_down;
set<pii> bridge_up, bridge_down;
// u < v
bool reach_up(int u, int v)
{
auto it = st_up.lower_bound(u);
return (it == st_up.end() || *it >= v);
}
// u > v
bool reach_down(int u, int v)
{
auto it = st_down.upper_bound(u);
if (it == st_down.begin()) return true;
--it;
return (*it <= v);
}
bool reach_updown(int u, int v)
{
auto it = bridge_up.lower_bound({u, -1});
if (it == bridge_up.end()) return false;
if (!reach_up(u, it->ff) || (it->ss > v && !reach_down(it->ss, v))) return false;
if (it->ss >= v) return true;
auto it2 = bridge_down.lower_bound({v, -1});
if (it2 == bridge_down.end() || !reach_down(it2->ff, v)) return false;
return (it2->ss >= u && reach_up(u, it2->ss));
}
bool reach_downup(int u, int v)
{
auto it = bridge_down.upper_bound({u, 1e9+10});
if (it == bridge_down.begin()) return false;
--it;
if (!reach_down(u, it->ff) || (it->ss < v && !reach_up(it->ss, v))) return false;
if (it->ss <= v) return true;
auto it2 = bridge_up.upper_bound({v, 1e9+10});
if (it2 == bridge_up.begin()) return false;
--it2;
if (!reach_up(it2->ff, v)) return false;
return (it2->ss <= u && reach_down(u, it2->ss));
}
int main(void)
{
int n, m;
scanf("%d %d", &n, &m);
while (m--)
{
char op;
int u, v;
scanf(" %c %d %d", &op, &u, &v);
if (op == 'A')
{
if (u > v) swap(u, v);
bridge_up.insert({u, v});
bridge_down.insert({v, u});
}
else if (op == 'B')
{
if (u > v) swap(u, v);
if (u <= n) st_up.insert({u, v});
else st_down.insert({v, u});
}
else
{
bool ok;
if (u <= n && v <= n)
{
if (u <= v) ok = reach_up(u, v);
else
{
auto it = bridge_up.lower_bound({u, -1});
if (it == bridge_up.end()) ok = false;
else ok = reach_downup(it->ss, v);
}
}
else if (u > n && v > n)
{
if (u >= v) ok = reach_down(u, v);
else
{
auto it = bridge_down.upper_bound({u, 1e9+10});
if (it == bridge_down.begin()) ok = false;
else
{
--it;
ok = reach_updown(it->ss, v);
}
}
}
else
{
if (u < v) ok = reach_updown(u, v);
else ok = reach_downup(u, v);
}
if (ok) printf("DA\n");
else printf("NE\n");
}
}
}
Compilation message
mostovi.cpp: In function 'int main()':
mostovi.cpp:73:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~~
mostovi.cpp:79:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf(" %c %d %d", &op, &u, &v);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
5 ms |
256 KB |
Output isn't correct |
2 |
Incorrect |
5 ms |
256 KB |
Output isn't correct |
3 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
4 |
Incorrect |
6 ms |
384 KB |
Output isn't correct |
5 |
Correct |
5 ms |
384 KB |
Output is correct |
6 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
7 |
Incorrect |
227 ms |
10008 KB |
Output isn't correct |
8 |
Incorrect |
233 ms |
9976 KB |
Output isn't correct |
9 |
Incorrect |
237 ms |
11512 KB |
Output isn't correct |
10 |
Incorrect |
271 ms |
11512 KB |
Output isn't correct |