#include <bits/stdc++.h>
using namespace std;
#define int long long
#define int long long
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define foru(i, l, r) for(int i = l; i <= r; i++)
#define ford(i, r, l) for(int i = r; i >= l; i--)
#define __TIME (1.0 * clock() / CLOCKS_PER_SEC)
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef pair<ii, ii> iiii;
const int N = 1e6 + 5;
const int oo = 1e9, mod = 1e9 + 7;
int n, m, k, q;
string s;
vector<ii> adj[N];
// precalc
void process() {
cin >> n >> m;
vector<vector<int>> c(n+1, vector<int>(n+1, oo));
foru(i,1,n) c[i][i]=0;
foru(i,1,m) {
int u, v, t; cin >> u >> v >> t;
u--, v--;
c[u][v]=min(c[u][v], t);
}
cin >> k >> q;
k = min(k, n);
auto sol = c;
while (--k) {
auto new_sol = sol;
for (int x = 0; x < n; x++)
for (int y = 0; y < n; y++)
for (int z = 0; z < n; z++)
new_sol[x][y] = min(new_sol[x][y], sol[x][z] + c[z][y]);
sol = new_sol;
}
while (q--) {
int s, t;
cin >> s >> t;
s--, t--;
if (sol[s][t]>=oo) cout << -1 << '\n'; else cout << sol[s][t] << '\n';
}
return;
}
signed main() {
cin.tie(0)->sync_with_stdio(false);
//freopen(".inp", "r", stdin);
//freopen(".out", "w", stdout);
process();
cerr << "Time elapsed: " << __TIME << " s.\n";
return 0;
}
/*
Xét các trường hợp đặc biệt
Kiểm tra lại input/output
Cố gắng trâu
Lật ngược bài toán
Keep calm and get VOI
Flow:
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
23900 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
6 ms |
23896 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
23900 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
23900 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
