// Om Namah Shivaya
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a, b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a, b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
refs:
official sol
https://github.com/galletas1712/CompetitiveProgramming/blob/master/Olympiad/Baltic/Baltic17-toll.cpp
queries => think if we can force segtree
to use segtree, we should be able to merge the left and right nodes efficiently
what info do we require to merge?
k is unusually small
we can look at the n points on a number line split into consecutive blocks of size = k
find min cost to go from block1[x] to block2[y]
if we have the min cost to go from left_most_block[i] to right_most_block[j] in the form of cost[i][j] for the left and right nodes, can we merge efficiently?
yes, we can merge in matmul style
build a segtree of matrices of dimensions k*k and use it to answer queries
(dnc prolly works faster than segtree)
*/
const int MOD = 1e9 + 7;
const int N = 5e4 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
const int K = 5;
int adj[N][K][K];
template<typename T>
struct segtree {
// https://codeforces.com/blog/entry/18051
/*=======================================================*/
struct data {
int a[K][K];
bool active;
data(){
memset(a,0x3f,sizeof a);
active = false;
}
};
data neutral = data();
data merge(data &left, data &right) {
if(!left.active) return right;
if(!right.active) return left;
data curr;
rep(x,K){
rep(y,K){
rep(z,K){
amin(curr.a[x][z], left.a[x][y] + right.a[y][z]);
}
}
}
return curr;
}
void create(int i) {
int block = i-n;
rep(x,K){
rep(y,K){
tr[i].a[x][y] = adj[block][x][y];
}
}
tr[i].active = 1;
}
void modify(int i, T v) {
}
/*=======================================================*/
int n;
vector<data> tr;
segtree() {
}
segtree(int siz) {
init(siz);
}
void init(int siz) {
n = siz;
tr.assign(2 * n, neutral);
}
void build(int siz) {
rep(i, siz) create(i + n);
rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
void pupd(int i, T v) {
modify(i + n, v);
for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
}
data query(int l, int r) {
data resl = neutral, resr = neutral;
for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
if (l & 1) resl = merge(resl, tr[l++]);
if (!(r & 1)) resr = merge(tr[r--], resr);
}
return merge(resl, resr);
}
};
void solve(int test_case)
{
int k,n,m,q; cin >> k >> n >> m >> q;
memset(adj,0x3f,sizeof adj);
rep(i,m){
int u,v,w; cin >> u >> v >> w;
adj[u/k][u%k][v%k] = w;
}
segtree<int> st(n+5);
st.build(n/k+1);
while(q--){
int u,v; cin >> u >> v;
int b1 = u/k, b2 = v/k;
int ans = -1;
if(b1 != b2) {
ans = st.query(b1,b2-1).a[u%k][v%k];
if(ans >= inf1){
ans = -1;
}
}
cout << ans << endl;
}
}
int main()
{
fastio;
int t = 1;
// cin >> t;
rep1(i, t) {
solve(i);
}
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
29 ms |
16296 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
38 ms |
16972 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
3 ms |
5204 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
3 ms |
5204 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
29 ms |
16296 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
