51 lines
1.4 KiB
C++
51 lines
1.4 KiB
C++
#include <bits/stdc++.h>
|
||
using namespace std;
|
||
const int N = 110, M = N << 1;
|
||
const int INF = 0x3f3f3f3f;
|
||
int n;
|
||
int x[N]; // 点权权值数组
|
||
int st[N]; // st 数组存是否遍历过这个节点
|
||
int dis[N][N]; // 存节点间的距离
|
||
|
||
// 链式前向星
|
||
int e[M], h[N], idx, w[M], ne[M];
|
||
void add(int a, int b, int c = 0) {
|
||
e[idx] = b, ne[idx] = h[a], w[idx] = c, h[a] = idx++;
|
||
}
|
||
|
||
void dfs(int root, int u, int step) { // root 表示根,u:当前走到哪个节点，step:到u点时走了几步
|
||
st[u] = 1; // u走过了，防止回头路
|
||
dis[root][u] = step, dis[u][root] = step; // root<->u之间的路径长度
|
||
|
||
for (int i = h[u]; ~i; i = ne[i]) {
|
||
int v = e[i];
|
||
if (st[v]) continue;
|
||
dfs(root, v, step + 1);
|
||
}
|
||
}
|
||
|
||
int main() {
|
||
// 初始化链式前向星
|
||
memset(h, -1, sizeof h);
|
||
|
||
cin >> n;
|
||
for (int i = 1; i <= n; i++) {
|
||
int a, b;
|
||
cin >> x[i] >> a >> b;
|
||
if (a) add(i, a), add(a, i); // 存图
|
||
if (b) add(i, b), add(b, i);
|
||
}
|
||
for (int i = 1; i <= n; i++) {
|
||
memset(st, 0, sizeof st);
|
||
dfs(i, i, 0); // 搜索
|
||
}
|
||
int ans = INF;
|
||
for (int i = 1; i <= n; i++) {
|
||
int s = 0;
|
||
for (int j = 1; j <= n; j++)
|
||
s = s + x[j] * dis[i][j]; // 累加距离
|
||
ans = min(ans, s);
|
||
}
|
||
cout << ans << endl;
|
||
return 0;
|
||
} |