NC111975(Legacy)
感受
思路
#include<bits/stdc++.h>
#define ls o << 1
#define rs o << 1 | 1
using namespace std;
typedef long long ll;
const int maxn = 1e6 + 10;
const int MAXN = 1e5 + 10;
const int inf = 0x3f3f3f3f;//1061109567 大约1e9 且inf + inf < int最大值
const ll INF = 0x3f3f3f3f3f3f3f3f;//4557430888798830399 大约4e18 且INF + INF < long long最大值
int n, q, s, tot;
int id[MAXN << 2][2];
struct Edge{
int from, to;
ll dis;
};
struct Node{
ll dis;///最短距离
int x;///顶点编号
bool operator < (const Node &a)const{
return dis > a.dis;
}
};
bool vis[maxn];
ll dis[maxn];
vector<Edge> G[maxn];
priority_queue<Node> que;
void add_edge(int u, int v, ll w){
G[u].push_back((Edge){u, v, w});
//cout << "(" << u << "," << v << ") = " << w << endl;
}
void dijkstra(int s){
for(int i = 1; i <= tot; i++){
dis[i] = INF;
vis[i] = false;
}
dis[s] = 0;
que.push((Node){0, s});
while(!que.empty()){
Node tmp = que.top(); que.pop();
int u = tmp.x;
if(vis[u]) continue;
vis[u] = true;
for(int i = 0; i < G[u].size(); i++){
Edge &e = G[u][i];
if(dis[e.to] > dis[e.from] + e.dis){
dis[e.to] = dis[e.from] + e.dis;
que.push((Node){dis[e.to], e.to});
}
}
}
}
void build(int o, int l, int r, int opt){
id[o][opt] = ++tot;
if(l == r){
add_edge(id[o][opt], l, 0);
add_edge(l, id[o][opt], 0);
return ;
}
int mid = (l + r) / 2;
build(ls, l, mid, opt);
build(rs, mid + 1, r, opt);
if(!opt){
add_edge(id[o][opt], id[ls][opt], 0);
add_edge(id[o][opt], id[rs][opt], 0);
}
else{
add_edge(id[ls][opt], id[o][opt], 0);
add_edge(id[rs][opt], id[o][opt], 0);
}
}
void update(int o, int l, int r, int x, int y, int opt, int u, ll w){
if(l >= x && y >= r){
if(!opt){
add_edge(u, id[o][opt], w);
}
else{
add_edge(id[o][opt], u, w);
}
return ;
}
int mid = (l + r) / 2;
if(mid >= x) update(ls, l, mid, x, y, opt, u, w);
if(y > mid) update(rs, mid + 1, r, x, y, opt, u, w);
}
int main(){
scanf("%d%d%d", &n, &q, &s);
tot = n;
build(1, 1, n, 0);
build(1, 1, n, 1);
int opt;
while(q--){
scanf("%d", &opt);
if(opt == 1){
int v, u; ll w;
scanf("%d%d%lld", &v, &u, &w);
add_edge(v, u, w);
}
else{
int v, l, r; ll w;
scanf("%d%d%d%lld", &v, &l, &r, &w);
update(1, 1, n, l, r, opt - 2, v, w);
}
}
dijkstra(s);
for(int i = 1; i <= n; i++){
printf("%lld%c", dis[i] == INF ? -1 : dis[i], i == n ? '\n' : ' ');
}
return 0;
}
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