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40 lines
847 B
C++
40 lines
847 B
C++
#include <bits/stdc++.h>
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using namespace std;
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int n, m, x, y, a, b;
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long double z, dist[2005], g[2005][2005];
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bool st[2005];
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void dijkstra() {
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for (int i = 1; i <= n; i++) {
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dist[i] = g[a][i];
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}
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dist[a] = 1;
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st[a] = true;
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for (int i = 1; i < n; i++) {
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int t = -1;
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for (int j = 1; j <= n; j++) {
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if (!st[j] && (t == -1 || dist[t] < dist[j])) {
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t = j;
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}
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}
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st[t] = true;
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for (int j = 1; j <= n; j++) {
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dist[j] = max(dist[j], dist[t] * g[t][j]);
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}
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}
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}
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int main() {
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cin >> n >> m;
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for (int i = 1; i <= m; i++) {
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cin >> x >> y >> z;
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g[x][y] = g[y][x] = (100 - z) / 100.00;
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}
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cin >> a >> b;
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dijkstra();
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cout << fixed << setprecision(8) << 100 / dist[b] << endl;
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return 0;
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}
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