P1744 采购特价商品

R53741022

Luogu/problem/P1744/P1744.cpp

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+#include <bits/stdc++.h>
+
+using namespace std;
+
+int n, m, x, y, s, t;
+double g[105][105];
+vector<pair<int, int>> d(1);
+
+double dis(pair<int, int> a, pair<int, int> b) {
+    return sqrt(pow(a.first - b.first, 2) + pow(a.second - b.second, 2));
+}
+
+int main() {
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> x >> y;
+        d.push_back(make_pair(x, y));
+    }
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= n; j++) {
+            g[i][j] = i == j ? 0 : 1e9;
+        }
+    }
+    cin >> m;
+    for (int i = 1; i <= m; i++) {
+        cin >> x >> y;
+        g[x][y] = g[y][x] = dis(d[x], d[y]);
+    }
+    for (int k = 1; k <= n; k++) {
+        for (int i = 1; i <= n; i++) {
+            for (int j = 1; j <= n; j++) {
+                g[i][j] = min(g[i][j], g[i][k] + g[k][j]);
+            }
+        }
+    }
+    cin >> s >> t;
+    cout << fixed << setprecision(2) << g[s][t] << endl;
+    return 0;
+}