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| #include <iostream>
#include <algorithm>
#include <map>
#include <vector>
#include <queue>
using namespace std;
#define INF 987654321
vector<pair<int,int>> v[20001];
int ans[20001];
int n, m, s, a, b, c;
bool cmp(pair<int, int>& a, pair<int, int>& b) {
return a.second < b.second;
}
struct p {
int n;
};
bool operator<(p a, p b) {
return ans[a.n] > ans[b.n];
}
void dijkstra(int cur) {
ans[cur] = 0;
priority_queue<p> q;
q.push(p{.n = cur});
int prev = 0;
while(!q.empty()) {
p c = q.top();
q.pop();
if(prev == c.n) continue;
prev = c.n;
for(auto it : v[c.n]) {
if(ans[it.first] > ans[c.n] + it.second) {
q.push(p{.n = it.first});
ans[it.first] = ans[c.n] + it.second;
}
}
}
}
void init() {
map<int,int> edge[20001];
scanf("%d %d %d",&n,&m,&s);
for(int i = 1; i <= n; ++i)
ans[i] = INF;
for(int i = 0; i < m; ++i) {
scanf("%d %d %d",&a,&b,&c);
edge[a][b] = edge[a][b] ? min(edge[a][b], c) : c;
}
for(int i = 1; i <= n; ++i) {
v[i].reserve(edge[i].size());
for(auto& it : edge[i])
v[i].push_back(it);
sort(v[i].begin(), v[i].end(), cmp);
}
}
int main() {
init();
dijkstra(s);
for(int i = 1; i <= n; ++i)
ans[i] == INF? printf("INF\n") : printf("%d\n",ans[i]);
}
|
