# | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
---|---|---|---|---|---|---|---|
651500 | alvinpiter | Toll (BOI17_toll) | C++17 | 0 ms | 0 KiB |
이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
/*
Picture the nodes are arranged in a 2D matrix with K rows
where each column contains nodes with the same floor(index/K).
dp[node][jump][k] = minimum cost to go from node "node" to the k-th node located in column node/K + 2^jump.
*/
#include<bits/stdc++.h>
using namespace std;
#define INF 1000000000
#define MAXN 50000
#define MAXLG 15
#define MAXK 5
int K, N, M, Q, dp[MAXN + 3][MAXLG + 3][MAXK + 3];
int bf(int a, int b) {
int ans = 0;
while (a != b) {
if (dp[a][0][0] < INF) {
ans += dp[a][0][0];
a += 1;
} else {
return -1;
}
}
return ans;
}
int main() {
cin >> K >> N >> M >> Q;
for (int i = 0; i < N; i++) {
for (int jump = 0; jump <= MAXLG; jump++) {
for (int k = 0; k <= K; k++) {
dp[i][jump][k] = INF;
}
}
}
for (int i = 0; i < M; i++) {
int a, b, t;
cin >> a >> b >> t;
dp[a][0][b%K] = t;
}
int numberOfColumns = N/K + (N%K == 0 ? 0 : 1);
for (int jump = 1; jump <= MAXLG; jump++) {
for (int i = 0; i < N; i++) {
int currentColumn = i/K;
int destinationColumn = currentColumn + (1 << jump);
if (destinationColumn >= numberOfColumns) {
continue;
}
for (int destinationK = 0; destinationK < K; destinationK++) {
for (int transitK = 0; transitK < K; transitK++) {
int transitColumn = currentColumn + (1 << (jump - 1));
int transitNode = transitColumn * K + transitK;
dp[i][jump][destinationK] = min(dp[i][jump][destinationK], dp[i][jump - 1][transitK] + dp[transitNode][jump - 1][destinationK]);
}
}
}
}
for (int q = 0; q < Q; q++) {
int a, b;
cin >> a >> b;
int currentColumn = a/K, destinationColumn = b/K;
int columnDiff = destinationColumn - currentColumn;
map<int, int> currentNodes;
currentNodes[a] = 0;
for (int jump = 0; jump <= MAXLG; jump++) {
if (columnDiff & (1 << jump)) {
map<int, int> newNodes;
for (auto [currentNode, currentCost]: currentNodes) {
for (int destinationK = 0; destinationK < K; destinationK++) {
int destinationColumn = currentColumn + (1 << jump);
int destinationNode = destinationColumn * K + destinationK;
int newCost = min(INF, currentCost + dp[currentNode][jump][destinationK]);
if (newNodes.find(destinationNode) == newNodes.end()) {
newNodes[destinationNode] = newCost;
} else {
newNodes[destinationNode] = min(newNodes[destinationNode], newCost);
}
}
}
swap(currentNodes, newNodes);
currentColumn += (1 << jump);
}
}
if (currentNodes.find(b) != currentNodes.end() && currentNodes[b] < INF) {
cout << ans << endl;
} else {
cout << -1 << endl;
}
}
}