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| #include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <algorithm>
#include <sstream>
#include <map>
#include <set>
#include <queue>
#define REP(i,k,n) for(int i=k;i<n;i++)
#define rep(i,n) for(int i=0;i<n;i++)
#define INF 1LL<<60
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
struct edge {
int from,to;
int cost;
edge(int t,int c) : to(t),cost(c) {}
edge(int f,int t,int c) : from(f),to(t),cost(c) {}
bool operator<(const edge &e) const {
return cost < e.cost;
}
};
vector<edge> G[100005];
ll d[100005];
bool used[100005];
void dijkstra(int s,int n) {
priority_queue<P,vector<P>,greater<P> > que;
fill(d,d+n,INF);
d[s] = 0;
que.push(P(0,s));
while(que.size()) {
P p = que.top();
que.pop();
int v = p.second;
if(d[v] < p.first) continue;
rep(i,G[v].size()) {
edge e = G[v][i];
if(d[e.to] > d[v] + e.cost) {
d[e.to] = d[v] + e.cost;
que.push(P(d[e.to],e.to));
}
}
}
}
int main() {
int n, m, c;
cin >> n >> m >> c;
ll sum = 0;
rep(i, m) {
int a, b, d;
cin >> a >> b >> d;
a--;
b--;
sum += d;
G[a].push_back(edge(b, d));
G[b].push_back(edge(a, d));
}
dijkstra(0, n);
vector<pair<ll, int> > v(n);
rep(i, n) {
v[i].first = d[i];
v[i].second = i;
}
sort(v.begin(), v.end());
memset(used, 0, sizeof(used));
ll ans = INF;
rep(i, v.size()) {
int j = v[i].second;
used[j] = true;
rep(k, G[j].size()) {
if(used[G[j][k].to]) {
sum -= G[j][k].cost;
}
}
ans = min(ans, d[j] * c + sum);
}
cout << ans << endl;
return 0;
}
|