#include<bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end()
using namespace std;
const int mxN = 2e5 + 227;
const int inf = 1e9 + 7;
int n;
int m;
int q;
int k;
vector<pair<int, int>> adj[mxN];
int idx[mxN];
int lvl[mxN];
struct SegmentTree{
struct Node{
int f[5][5];
int lef;
int rig;
};
int n;
vector<Node> t;
Node base;
SegmentTree(){}
SegmentTree(int _n){
n = _n;
t.resize(n * 4 + 7);
}
Node mergenode(Node &x, Node &y)
{
if(x.lef == -1) return y;
if(y.lef == -1) return x;
Node res;
res.lef = x.lef;
res.rig = y.rig;
// a - > b - > c -> d
// b -> c
for(int i = 0; i < k; i++)
for(int j = 0; j < k; j++) res.f[i][j] = inf;
for(int a = 0; a < k; a++)
for(int b = 0; b < k; b++) {
if(x.f[a][b] == inf) continue;
for(auto it : adj[x.rig * k + b]) {
int c = idx[it.fi];
int cost = it.se;
for(int d = 0; d < k; d++) {
if(y.f[c][d] == inf) continue;
res.f[a][d] = min(res.f[a][d], x.f[a][b] + cost + y.f[c][d]);
}
}
}
return res;
}
void build(int v, int tl, int tr)
{
if(tl == tr) {
t[v].lef = t[v].rig = tl - 1;
for(int i = 0; i < k; i++)
for(int j = 0; j < k; j++)
if(i == j) t[v].f[i][j] = 0;
else t[v].f[i][j] = inf;
}
else {
int tm = (tl + tr) / 2;
build(v * 2, tl, tm);
build(v * 2 + 1, tm + 1, tr);
t[v] = mergenode(t[v * 2], t[v * 2 + 1]);
}
}
Node query(int v, int tl, int tr, int l, int r)
{
if(l > r) return base;
if(tl == l && tr == r) return t[v];
else {
int tm = (tl + tr) / 2;
Node m1 = query(v * 2, tl, tm, l, min(r, tm));
Node m2 = query(v * 2 + 1, tm + 1, tr, max(l, tm + 1), r);
Node rr = mergenode(m1, m2);
return rr;
}
}
int query(int l, int r, int x, int y)
{
Node res = query(1, 1, n, l, r);
return res.f[x][y];
}
} seg;
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
//freopen("task.inp", "r", stdin);
//freopen("task.out", "w", stdout);
cin >> k >> n >> m >> q;
for(int i = 1; i <= m; i++) {
int u, v, c;
cin >> u >> v >> c;
adj[u].pb({v, c});
adj[v].pb({u, c});
}
for(int i = 0; i < n; i++) {
lvl[i] = i / k;
idx[i] = i % k;
}
seg = SegmentTree(n / k + 7);
seg.build(1, 1, n / k + 7);
seg.base.lef = -1;
while(q--) {
int u, v;
cin >> u >> v;
//cout << lvl[u] << ' ' << lvl[v] << ' ' << idx[u] << ' ' << idx[v] << endl;
int res = seg.query(lvl[u] + 1, lvl[v] + 1, idx[u], idx[v]);
if(res == inf) cout << -1 << '\n';
else cout << res << '\n';
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
63 ms |
29132 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
63 ms |
20336 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
4948 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
3 ms |
4948 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
63 ms |
29132 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |