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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#168116 | #5458. Shortest Path Query | syksykCCC | TL | 2ms | 6224kb | C++14 | 1.6kb | 2023-09-07 21:42:24 | 2023-09-07 21:42:24 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 5e4 + 5, M = 1e5 + 5;
vector<pair<int, int>> G[N], conv[N]; // (w = 0, w = 1)
int n, m, q;
void add(vector<pair<int, int>> &c, int x, int y) {
if(c.empty()) { c.emplace_back(x, y); return; }
if(c.back().first == x) y = min(c.back().second, y), c.pop_back();
while(c.size() > 1) {
int e = (int)c.size() - 1;
if((ll)(c[e-1].second - c[e].second) * (c[e].first - x)
< (ll)(c[e-1].second - y) * (c[e-1].first - c[e].first)) c.pop_back();
else break;
}
c.emplace_back(x, y);
}
vector<pair<int, int>> merge(const vector<pair<int, int>> &A, const vector<pair<int, int>> &B, int dx, int dy) {
int i = 0, j = 0;
vector<pair<int, int>> res;
while(i < A.size() && j < B.size()) {
if(A[i].first <= B[i].first + dx) add(res, A[i].first, A[i].second), i++;
else add(res, B[j].first + dx, B[j].second + dy), j++;
}
for(; i < A.size(); i++) add(res, A[i].first, A[i].second);
for(; j < B.size(); j++) add(res, B[j].first + dx, B[j].second + dy);
return res;
}
int main() {
scanf("%d %d", &n, &m);
for(int i = 1; i <= m; i++) {
int u, v, c;
scanf("%d %d %d", &u, &v, &c);
G[v].emplace_back(u, c); // reversed edge
}
conv[1].emplace_back(0, 0);
for(int u = 2; u <= n; u++) {
for(auto e : G[u]) {
int v = e.first, w = e.second;
conv[u] = merge(conv[u], conv[v], w == 0, w == 1);
}
}
scanf("%d", &q);
while(q--) {
int a, b, x;
scanf("%d %d %d", &a, &b, &x);
ll ans = LLONG_MAX;
for(auto p : conv[x]) {
ans = min(ans, (ll)a * p.first + (ll)b * p.second);
}
printf("%lld\n", ans);
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 2ms
memory: 6224kb
input:
4 4 1 2 0 1 3 1 2 4 0 3 4 1 3 3 5 2 3 2 4 2 3 4
output:
3 4 4
result:
ok 3 number(s): "3 4 4"
Test #2:
score: -100
Memory Limit Exceeded
input:
50000 100000 1 2 1 2 3 0 3 4 1 4 5 0 5 6 1 6 7 0 7 8 1 8 9 1 9 10 0 10 11 1 11 12 1 12 13 1 13 14 0 14 15 0 15 16 0 16 17 0 17 18 1 18 19 1 19 20 0 20 21 1 21 22 0 22 23 0 23 24 1 24 25 1 25 26 0 26 27 1 27 28 0 28 29 0 29 30 0 30 31 0 31 32 1 32 33 0 33 34 1 34 35 1 35 36 1 36 37 1 37 38 0 38 39 0 ...